Lens drive apparatus

ABSTRACT

A lens drive apparatus includes a plurality of protrusions that protrude from an end of a magnet holder in a direction of an optical axis toward an inner wall surface of a cover and function as a fracture prevention supporting member. The plurality of protrusions are configured to support prevention of fracture in a plurality of suspension wires by contacting the inner wall surface of the cover when a magnet holder moves in the direction of the optical axis.

The present application is continuation of application Ser. No.15/688,923, filed Aug. 29, 2017, which is continuation of applicationSer. No. 14/832,009, filed Aug. 21, 2015, now U.S. Pat. No. 9,778,481,which is continuation of application Ser. No. 13/586,235, filed Aug. 15,2012, now U.S. Pat. No. 9,151,963; which claims the benefit of priorityfrom Japanese Patent Application No. 2011-182462, filed on Aug. 24,2011; and Japanese Patent Application No. 2012-81688, filed on Mar. 30,2012, the disclosures of which are incorporated herein in their entiretyby reference.

BACKGROUND OF THE INVENTION

This invention relates to a lens holder driving device and, inparticular, to a lens holder driving device capable of picking up astill image without blurry images by stabilizing the blurry images(movement) occurring upon shooting the still image using a miniaturecamera for a mobile terminal.

Hitherto, various lens holder driving devices has been proposed whichare capable of taking photographs with a high degree by stabilizingblurry images on an image-forming surface although there are blurryimages (movement) upon shooting the still image.

By way of illustration, two of the present co-inventors proposed animage stabilizer which is capable of miniaturizing and lowering a heightby sharing a permanent magnet for an auto-focusing (AF) lens drivingdevice as a permanent magnet for the image stabilizer (see, JapaneseUnexamined Patent Application Publication No. 2011-65140(JP-A-2011-065140) (which will be also called Patent Document 1)).

The image stabilizer disclosed in Patent Document 1 is called an imagestabilizer of “a barrel shift method” because blurry images arestabilized by moving a lens barrel received in an AF lens driving device(a lens holder moving portion) in itself. In addition, the imagestabilizers of “the barrel shift method” are classified into “a movingmagnet method” in which the permanent magnet moves (is movable) and “amoving coil method” in which the coil moves (is movable).

Patent Document 1 discloses, as the image stabilizer of “the movingmagnet method” in a second exemplary embodiment thereof, an imagestabilizer which is provided with a permanent magnet comprising fourfirst permanent magnet pieces and four second permanent magnet pieceswhich are disposed so as to apart from up and down in a direction of anoptical axis and which is provided with a stabilizer coil disposedbetween the upper four first permanent magnet pieces and the lower foursecond permanent magnet pieces. That is, the second exemplary embodimentcomprises the image stabilizer of “the moving magnet method” includingthe permanent magnet comprising eight permanent magnet pieces in total.

In the image stabilizer disclosed in Patent Document 1, a base isdisposed so as to apart from at a bottom portion of the auto-focusinglens driving device and a plurality of suspension wires have one endswhich are fixed to the base at outer regions thereof. The plurality ofsuspension wires has other ends which are firmly fixed to theauto-focusing lens driving device (the lens holder moving portion).

In the image stabilizer disclosed in Patent Document 1, the plurality ofsuspension wires swingably support the auto-focusing lens driving device(the lens holder moving portion). Therefore, there is a problem in whichthe auto-focusing lens driving device (the lens holder moving portion)resonates undesirably.

Japanese Unexamined Patent Application Publication No. 2011-85666(JP-A-2011-085666) (which will be also called Patent Document 2) alsodiscloses a lens driving device which shares an AF control magnet as animage stabilizer control magnet. The lens driving device disclosed inPatent Document 2 comprises a lens holder including a first coil (an AFcoil) disposed at an outer periphery of a lens, a magnet holderconfigured to fix a magnet having a first surface facing the first coil,springs for supporting the lens holder so as to couple the lens holderwith the magnet holder and also so that the lens holder is moved withrespect to the magnet in a direction of an optical axis, and a basemember configured so that a second coil (an image stabilizer coil) isfixed to face a second surface of the magnet that is perpendicular tothe first surface thereof. A lens holding unit, which comprises the lensholder, the magnet, the magnet holder, and the springs, is held so as tobe relatively movable in a direction perpendicular to the optical axisrelative to the base member.

Patent Document 2 discloses the lens driving device as a six exemplaryembodiment in which a position detection sensor is disposed at aclearance of the image stabilizer coil wound. A Hall element is used asthe position detection sensor. In addition, the lens holding unit isheld by four suspension wires which are disposed to a fixed portion atfour corners thereof. That is, the four suspension wires have one endsfixed to the four corners of the fixed portion and other ends which arefirmly fixed to the lens holding unit.

In also the lens driving device disclosed in Patent Document 2, the foursuspension wires swingably support the lens holding unit. As a result,in the manner similar to the image stabilizer disclosed in PatentDocument 1, there is a problem in which the lens holding unit resonatesundesirably.

Accordingly, it is impossible to carry out operation with stability inthe devices disclosed in Patent Documents 1 and 2.

On the other hand, Japanese Unexamined Patent Application PublicationNo. 2009-145771 (JP-A-2009-145771) (which will be also called PatentDocument 3) discloses “an image stabilizing device” which is capable ofreducing influence of unnecessary resonance. The image stabilizingdevice disclosed in Patent Document 3 comprises a movable member forholding stabilizing means for stabilizing blurred images, a fixed membersupporting the movable member movably within a plane orthogonal to anoptical axis of an image pickup optical system, driving means changing arelative position of the movable member with respect to the fixedmember, and damping means disposed between the movable member and thefixed member. In Patent Document 3, by arranging the damping means tosuitable positions, resonance of translational motion which is motionwithin the plane orthogonal to the optical axis and resonance byrotation around the optical axis are suppressed (attenuated).

The image stabilizing device disclosed in Patent Document 3 merelysuppresses (attenuates) the resonance by movement (the translationalmotion and the rotation around the optical axis) on the plane orthogonalto the optical axis.

SUMMARY OF THE INVENTION

It is therefore an exemplary object of the present invention to providea lens holder driving device which is capable of carrying out operationwith stability.

Other objects of this invention will become clear as the descriptionproceeds.

On describing the gist of an exemplary aspect of this invention, it ispossible to be understood that a lens holder driving device comprises alens holder moving portion in which a lens holder moves in a directionof an optical axis and in first and second directions which areorthogonal to the optical axis and which are perpendicular to eachother, and a fixed member disposed apart from the lens holder movingportion in the direction of the optical axis. According to the exemplaryaspect of this invention, the lens holder driving device comprises: anelastic member mounted to the lens holder moving portion; a plurality ofsuspension wires having first end portions fixed to the fixed member atouter regions thereof, extending along the optical axis, having secondend portions fixed to the elastic member, and swingably supporting thelens holder moving portion in the first direction and the seconddirection; and at least one damper compound disposed so as to enclose atleast one suspension wire among the plurality of suspension wires tosuppress undesired resonance in the lens holder moving portion.

BRIEF DESCRIPTION OF THE DRAWING

FIG. 1 is an external perspective view of a lens holder driving deviceaccording to a first exemplary embodiment of the present invention;

FIG. 2 is a partial vertical cross sectional view of the lens holderdriving device illustrated in FIG. 1;

FIG. 3 is an exploded perspective view of the lens holder driving deviceillustrated in FIG. 1;

FIG. 4 is a perspective view of a coil board and an image stabilizercoil (a driving coil) formed therein which are used in the lens holderdriving device illustrated in FIG. 1;

FIG. 5 is a perspective view showing a relationship between a relatedmagnetic circuit and Hall elements;

FIG. 6 is a vertical cross sectional view showing a relationship betweenthe related magnetic circuit and the Hall elements;

FIG. 7 is a vertical cross sectional view shoring a relationship betweenthe related magnetic circuit and the Hall elements in a case ofdisplacing an AF unit in a fore-and-aft direction X;

FIG. 8 is a view showing a frequency response of a front-side Hallelement in the related magnetic circuit;

FIGS. 9A, 9B, and 9C are views showing relationships between phases andmagnitudes among a magnetic flux density a of a magnetic field Bgenerated by the a front-side permanent magnetic piece, a magnetic fluxdensity b of a magnetic field B₁₁ generated by a first IS currentI_(IS1) flowing through a front-side image stabilizer coil, and a totalmagnetic flux density (a+b) detected by the front-side Hall element in aregion I, a region II, and a region III of FIG. 8, respectively;

FIG. 10 is a view tabulated for the relationships of FIGS. 9A-9C;

FIG. 11 is a perspective view showing a relationship between a magneticcircuit and Hall elements for use in the lens holder driving deviceillustrated in FIG. 1;

FIG. 12 is a vertical cross sectional view showing a relationshipbetween the magnetic circuit and the Hall elements illustrated in FIG.11;

FIG. 13 is a vertical cross sectional view showing a relationshipbetween the magnetic circuit and the Hall elements illustrated in FIG.11 in a case of displacing an AF unit in an fore-and-aft direction X;

FIG. 14 is a cross sectional view taken on line XIV-XIV of FIG. 13;

FIG. 15 is a view showing a frequency response of a front-side Hallelement in the magnetic circuit illustrated in FIG. 11;

FIGS. 16A, 16B, and 16C are views showing relationships between phasesand magnitudes among a magnetic flux density a of a magnetic field Bgenerated by the a front-side permanent magnetic piece, a magnetic fluxdensity b of a magnetic field B₁₁ generated by a first IS current IIS1flowing in a front-side image stabilizer coil, and a total magnetic fluxdensity (a+b) detected by the front-side Hall element in a region I, aregion II, and a region III of FIG. 15, respectively;

FIG. 17 is a view tabulated for the relationships of FIGS. 16A-160;

FIG. 18 is a cross sectional view showing a relationship of a placementamong one permanent magnet piece of the permanent magnet, a focusingcoil disposed around it, and an image stabilizer coil (a driving coil)in the magnetic circuit illustrated in FIG. 11;

FIG. 19 is a partial perspective view enlargedly showing a part fixing asecond end portion of a suspension wire to an upper leaf spring for usein the lens holder driving device illustrated in FIG. 1;

FIG. 20 is a partial cross sectional view of the fixed part illustratedin FIG. 19;

FIG. 21 is a perspective view showing a assembly of a coil board and aflexible printed circuit (FPC) for use in the lens holder driving deviceillustrated in FIG. 1 seen from a rear side;

FIG. 22 is a plan view showing a state where a shielding cover isomitted from the lens holder driving device illustrated in FIG. 1;

FIG. 23 is a partial enlarged perspective view enlargedly showing atied-up part of an end portion of a wire composed of the focusing coilin FIG. 22;

FIG. 24 is a fragmentary vertical sectional view showing a state where ashielding cover is omitted from the lens holder driving deviceillustrated in FIG. 1;

FIG. 25 is a fragmentary perspective view of the lens holder drivingdevice illustrated in FIG. 24 seen from a slanting above;

FIG. 26 is a fragmentary sectional view of the lens holder drivingdevice in a case without any damper compound in the lens holder drivingdevice illustrated in FIG. 24;

FIG. 27 is a fragmentary sectional view of the lens holder drivingdevice in a case with damper compounds in the lens holder driving deviceillustrated in FIG. 24;

FIG. 28 is a view showing a frequency response of an auto-focusing lensdriving portion (a lens holder moving portion) of a conventional lensholder device without the damper compounds in directions perpendicularto an optical axis;

FIG. 29 is a view showing a frequency response of an auto-focusing lensdriving portion (a lens holder moving portion) of the lens holder deviceaccording to the first exemplary embodiment of the present invention indirections perpendicular to an optical axis;

FIG. 30 is a plan view showing an arrangement position of a dampercompound in a lens holder driving device according to a first modifiedexample of the first exemplary embodiment with a shielding cover omittedtherefrom and with a part of an upper leaf spring (a first leaf spring)omitted therefrom;

FIG. 31 is a plan view showing arrangement positions of damper compoundsin a lens holder driving device according to a second modified exampleof the first exemplary embodiment with the shielding cover omittedtherefrom and with the part of the upper leaf spring (the first leafspring) omitted therefrom;

FIG. 32 is an external perspective view of a camera module comprisingthe lens holder driving device according to the first exemplaryembodiment;

FIG. 33 is an exploded perspective view showing the camera moduleillustrated in FIG. 32;

FIG. 34 is a perspective view showing appearance of a camera-equippedmobile terminal comprising the camera module illustrated in FIG. 33;

FIG. 35 is an external perspective view of a lens holder driving deviceaccording to a second exemplary embodiment of the present invention;

FIG. 36 is a partial vertical cross sectional view of the lens holderdriving device illustrated in FIG. 35;

FIG. 37 is an exploded perspective view of the lens holder drivingdevice illustrated in FIG. 35;

FIG. 38 is a partial perspective view enlargedly showing a part fixing asecond end portion of a suspension wire to an upper leaf spring for usein the lens holder driving device illustrated in FIG. 35;

FIG. 39 is a partial cross sectional view of the fixed part illustratedin FIG. 38;

FIG. 40 is a plan view showing a state where a shielding cover isomitted from the lens holder driving device illustrated in FIG. 35;

FIG. 41 is a fragmentary vertical sectional view showing a state wherethe shielding cover is omitted from the lens holder driving deviceillustrated in FIG. 35;

FIG. 42 is a fragmentary perspective view of the lens holder drivingdevice illustrated in FIG. 41 seen from a slanting above;

FIG. 43 is a plan view showing arrangement positions of damper compoundsin the lens holder driving device illustrated in FIG. 41 with a part ofan upper leaf spring (a first leaf spring) omitted therefrom;

FIG. 44 is a view showing a frequency response of an auto-focusing lensdriving portion of a conventional lens holder device without the dampercompounds in a direction of an optical axis;

FIG. 45 is a view showing a frequency response of an auto-focusing lensdriving portion of the lens holder driving device according to thesecond exemplary embodiment of the present invention in a direction ofan optical axis;

FIG. 46 is a plan view showing an arrangement position of a dampercompound in a lens holder driving device according to a first modifiedexample of the second exemplary embodiment with a shielding coveromitted therefrom and with a part of an upper leaf spring (a first leafspring) omitted therefrom;

FIG. 47 is a plan view showing arrangement positions of damper compoundsin a lens holder driving device according to a second modified exampleof the second exemplary embodiment with the shielding cover omittedtherefrom and with the part of the upper leaf spring (the first leafspring) omitted therefrom;

FIG. 48 is a plan view showing arrangement positions of damper compoundsin a lens holder driving device according to a third modified example ofthe second exemplary embodiment with the shielding cover omittedtherefrom and with the part of the upper leaf spring (the first leafspring) omitted therefrom;

FIG. 49 is a fragmentary vertical sectional view showing a state where ashielding cover is omitted from a lens holder driving device accordingto a fourth modified example of the second exemplary embodiment;

FIG. 50 is a vertical cross sectional view of a lens holder drivingdevice according to a third exemplary embodiment of the presentinvention; and

FIG. 51 is an exploded perspective view of the lens holder drivingdevice illustrated in FIG. 50.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring now to Figures, the description will proceed to exemplaryembodiments of the present invention.

First Exemplary Embodiment

Referring to FIGS. 1 through 3, the description will proceed to a lensholder driving device 10 according to a first exemplary embodiment ofthis invention. FIG. 1 is an external perspective view of the lensholder driving device 10. FIG. 2 is a partial vertical cross sectionalview of the lens holder driving device 10. FIG. 3 is an explodedperspective view of the lens holder driving device 10.

Herein, in the manner shown in FIGS. 1 through 3, an orthogonalcoordinate system (X, Y, Z) is used. In a state illustrated in FIGS. 1through 3, in the orthogonal coordinate system (X, Y, X), an X-axisdirection is a fore-and-aft direction (a depth direction), a Y-axisdirection is a left-and-right direction (a width direction), and aZ-axis direction is an up-and-down direction (a height direction). Inaddition, in the example being illustrated in FIGS. 1 through 3, theup-and-down direction Z is a direction of an optical axis O of a lens.In the first exemplary embodiment, the X-axis direction (thefore-and-aft direction) is called a first direction while the Y-axisdirection (the left-and-right direction) is called in a seconddirection.

However, in an actual use situation, the direction of the optical axisO, namely, the Z-axis direction becomes a fore-and-aft direction. Inother words, an upper direction of the Z-axis becomes a front directionwhile a lower direction of the Z-axis becomes a rear direction.

The illustrated lens driving device 10 is mounted to a mobile terminalsuch as a camera-equipped cellular mobile phone which is enable toautomatic focusing, a smart phone, a notebook personal computer, atablet-type personal computer, a mobile-type game machine, a Web camera,a vehicle-mounted camera, or the like. The lens holder driving device 10comprises an auto-focusing lens holder driving portion 20 which willlater be described, and an image stabilizer portion (which will later bedescribed) for stabilizing blurry images (vibrations) occurring in theauto-focusing lens holder driving portion 20 upon shooting a still imageusing a miniature camera for the mobile terminal and is a device whichis capable of picking up the still image without image blurred. Theimage stabilizer portion of the lens holder driving device 10 stabilizesthe blurry images by moving the auto-focusing lens holder drivingportion 20 in the first direction (the fore-and-aft direction) X and thesecond direction (the left-and-right direction) Y which are orthogonalto the optical axis O and which are perpendicular to each other.

In other words, the illustrated lens holder driving device 10 comprisesa lens holder moving portion (which will later be described) in which alens holder 24 moves in an optical axis O and in the first direction(the fore-and-aft direction) X and the second direction (theleft-and-right direction) Y which are orthogonal to the optical axis Oand which are perpendicular to each other, and a fixed member 13 (whichwill later be described) disposed apart from the lens holder movingportion in the direction of the optical axis O.

The auto-focusing lens holder driving portion 20 is for moving the lensholder 14 (which will later be described) capable of mounting a lensbarrel 12 (see, FIG. 33) along the optical axis O. Apart from a bottomportion of the auto-focusing lens holder driving portion 20, the fixedmember 13 is disposed. Although illustration is not made, the fixedmember 13 has a lower portion (a rear portion) on which an image pickupdevice (a sensor) 76 (see, FIG. 33) disposed on a sensor board 72 (see,FIG. 33) is mounted. The image pickup device 76 picks up a subject imageformed by the lens barrel 12 to convert it into an electric signal. Theimage pickup device 76 may, for example, comprise a CCD (charge coupleddevice) type image sensor, a CMOS (complementary metal oxidesemiconductor) type image sensor, or the like. Accordingly, a cameramodule 70 (see, FIG. 33) comprises a combination of the lens barrel 12,the auto-focusing lens holder driving portion 20, the sensor board 72,and the image pickup device 76.

The fixed member 13 comprises a base 14, a coil board 40, an imagestabilizer coil (a driving coil) 18, a flexible printed circuit (FPC)44.

The base 14 has a ring-shaped which has the outside shape of arectangular and which has a circular opening 14 a in the interiorthereof.

The image stabilizer portion of the lens holder driving device 10comprises four suspension wires 16 having first end portions 161 fixedto four corner portions of the fixed member 13, and the image stabilizercoil (the driving coil) 18 disposed to face a permanent magnet 28 of theauto-focusing lens holder driving portion 20 (which will later bedescribed) in the manner which will later be described.

The four suspension wires 16 extend along the optical axis O andswingably support the auto-focusing lens holder driving portion 20 (thelens holder moving portion) as a whole in the first direction (thefore-and-aft direction) X and the second direction (the left-and-rightdirection) Y. The four suspension wires 16 have second end portions 162which are fixed to an upper end portion of the above-mentionedauto-focusing lens holder driving portion 20 in the manner which willlater be described.

In the manner described above, the four suspension wires 16 serves as asupporting member for swingably supporting the auto-focusing lens holderdriving portion 20 with respect to the fixed member 13 in the firstdirection Y and the second direction Y.

The image stabilizer portion of the lens holder driving device 10comprises the coil board 40 having a rectangular ring shape that isdisposed apart from to face the permanent magnet 28 in the manner whichwill later be described. The coil board 40 is mounted on the base 14with the flexible printed circuit (FPC) 44 which will later be describedis sandwiched therebetween. The above-mentioned image stabilizer coil(the driving coil) 18 is formed on the coil board 40.

In the manner which is described above, the fixed member 13 comprises acombination of the base 14, the coil board 40, the image stabilizer coil(the driving coil) 18, and the flexible printed circuit (FPC) 44.

Referring now to FIG. 3, the description will proceed to theauto-focusing lens holder driving portion 20. The auto-focusing lensholder driving portion 20 is also called an AF unit.

The auto-focusing lens holder driving portion 20 comprises theabove-mentioned lens holder 24 including a tubular portion 240 forholding the lens barrel 12, a ring-shaped focusing coil 26 fixed to thelens holder 24 so as to position around the tubular portion 240 thereof,a magnet holder 30 for holding the permanent magnet 28 disposed oppositeto the focusing coil 26 at the outside of the focusing coil 26, andfirst and second leaf springs 32 and 34 mounted on first and second ends30 a and 30 b of the magnetic holder 30 in the direction of the opticalaxis O, respectively. The first and the second leaf springs 32 and 34are collectively called an elastic member (32, 34).

In addition, a combination of the focusing coil 26, the permanent magnet28, and the magnet holder 30 constitutes the above-mentioned lens holdermoving portion (26, 28, 30). In other words, the lens holder movingportion (26, 28, 30) is a portion where the lens holder 24, the elasticmember (32, 34), and a spacer 36 (which will later be described) areomitted from the auto-focusing lens holder driving portion 20.

The first and second springs 32 and 34 support the lens holder 24 in thedirection of the optical axis O shiftably so as to position the lensholder 24 in a radial direction. In the example being illustrated, thefirst leaf spring 32 is called an upper leaf spring while the secondleaf spring 34 is called a lower leaf spring.

In addition, in the manner which is described above, in the actual usesituation, the upper direction in the Z-axis direction (the direction ofthe optical axis O) becomes the front direction while the lowerdirection in the Z-axis direction (the direction of the optical axis O)becomes the rear direction. Accordingly, the upper leaf spring 32 isalso called a front-side spring while the lower leaf spring 34 is alsocalled a rear-side spring.

The magnet holder 30 has configuration of a substantially octagonaltube. Specifically, the magnet holder 30 comprises an outer tubularportion 302 having an octagonal tubular shape, an octagonal upperring-shaped end portion 304 provided at an upper end (a front end, thefirst end) 30 a of the outer tubular portion 302, and an octagonal lowerring-shaped end portion 306 provided at a lower end (a rear end, thesecond end) 30 b of the outer tubular portion 302. The upper ring-shapedend portion 304 has eight upper protrusions 304 a which project at fourcorners upwards by two per corner. The lower ring-shaped end portion 306has four lower protrusions 306 a which project at four cornersdownwards.

The focusing coil 26 has an octagonal cylindrical shape which coincideswith an outer shape of the magnet holder 30 having the octagonal tubularshape. The permanent magnet 28 comprises four rectangular permanentmagnet pieces 282 which are disposed in the outer tubular portion 302having the octagonal tubular shape in the magnet holder 30 so as toapart from each other in the first direction (the fore-and-aftdirection) X and the second direction (the left-and-right direction) Y.The four permanent magnet pieces 282 are disposed with spaces betweenthem and the focusing coil 26. In the example being illustrated, eachpermanent magnet piece 282 has an inner end side polarised (magnetized)to the north pole and an outer end side polarised (magnetized) to thesouth pole.

The upper leaf spring (the front-side spring) 32 is disposed at an upperside (a front side) of the lens holder 24 in the direction of theoptical axis O while the lower leaf spring (the rear-side spring) 34 isdisposed at a lower side (a rear side) of the lens holder 24 in thedirection of the optical axis O.

The upper leaf spring (the front-side spring) 32 comprises an upperinner end portion 322 mounted on an upper end portion of the lens holder24 in the manner which will later be described and an upper outer endportion 324 mounted on the upper ring-shaped end portion 304 of themagnet holder 30 in the manner which will later be described. Betweenthe upper inner end portion 322 and the upper outer end portion 324, aplurality of upper arm portions 326 are provided. That is, the pluralityof upper arm portions 326 connects the upper inner end portion 322 tothe upper outer end portion 324.

The tubular portion 240 of the lens holder 24 has, at an upper endthereof, four upper protrusions 240 a projecting at four cornersupwards. The upper inner end portion 322 has four upper holes 322 a inwhich the four upper protrusions 240 a are compression inserted(charged), respectively. That is, the four upper protrusions 240 a ofthe tubular portion 240 of the lens holder 243 are compression inserted(charged) in the four upper holes 322 a of the upper inner end portion322 of the upper leaf spring 32, respectively.

On the other hand, the upper outer end portion 324 has eight upper holes324 a in which the eight upper protrusions 34 a of the magnet holder 30are charged, respectively. That is, the eight upper protrusions 34 a ofthe magnet holder 30 are charged in the eight upper holes 324 a of theupper outer end portion 324.

The upper leaf spring (the front-side spring) 32 further comprises fourarc-shaped extending portions 328 which extend at four corers of theupper outer end portion 324 in the radial direction outwards. The fourarc-shaped extending portions 328 have four wire fixing holes 328 a inwhich the second end portions 162 of the four suspension wires 16 areinserted (charged), respectively. A detailed structure of eacharc-shaped extending portion 328 will later be described with referenceto FIG. 19 in detail.

The lower leaf spring (the rear-side spring) 34 comprises a lower innerend portion 342 mounted on a lower end portion of the lens holder 24 inthe manner which will later be described and a lower outer end portion344 mounted on the lower ring-shaped end portion 306 of the magnetholder 30 in the manner which will later be described. Between the lowerinner end portion 342 and the lower outer end portion 344, a pluralityof lower arm portions 346 are provided. That is, the plurality of lowerarm portions 346 connects the lower inner end portion 342 to the lowerouter end portion 344.

The lower leaf spring 34 has a lower portion in which a spacer 36 havinga substantially same outside shape is disposed. More specifically, thespacer 36 comprises an outer ring portion 364 having a shape which issubstantially equivalent to that of the lower outer end portion 344 ofthe lower leaf spring 34 and an inner ring portion 362 having a shape soas to cover the lower inner end portion 342 and the lower arm portions346 of the lower leaf spring.

The tubular portion 240 of the lens holder 24 has, at a lower end, fourlower protrusions (not shown) projecting at four corners downwards. Thelower inner end portion 342 has four lower holes 342 a in which the fourlower protrusions are compression inserted (charged), respectively. Thatis, the four lower protrusions of the tubular portion 240 of the lensholder 24 are compression inserted (charged) in the four lower holes 342a of the lower inner end portion 342 of the lower leaf spring 34.

On the other hand, the lower outer end portion 344 of the lower leafspring 34 has four lower holes 344 a in which the four lower protrusions306 a of the magnet holder 30 are charged, respectively. The outer ringportion 364 of the spacer 36 also has four lower holes 364 a in whichthe four lower protrusions 306 a of the magnet holder 30 are compressioninserted at positions corresponding to the four lower holes 344 a,respectively. That is, the four lower protrusions 306 a of the magnetholder 30 are compression inserted in the four lower holes 364 a of theouter ring portion 364 of the spacer 36 via the four lower holes 344 aof the lower outer end portion 344 of the lower leaf spring 34,respectively, to be thermally welded at tips thereof.

As apparent from FIG. 2, the four lower protrusions 306 a of the magnetholder 30 project so as to get near toward the coil board 40. In otherwords, it is understood that clearance between the four lowerprotrusions 306 a and the coil board 40 becomes narrow in comparisonwith clearance in other areas (i.e. clearance between the spacer 36 andthe coil board 40).

The elastic member (32, 34) comprising the upper leaf spring 32 and thelower leaf spring 34 serves as a guiding arrangement for guiding thelens holder 24 so as to be movable in the direction of the optical axisO alone. Each of the upper leaf spring 32 and the lower leaf spring 34comprises a spring member made of beryllium copper, nickel copper,stainless steel, or the like.

The tubular portion 240 of the lens holder 24 has an inner wall in whicha female screw thread (not shown) is cut. On the other hand, althoughthe illustration is not made, the lens barrel 12 has an outer wall inwhich a male screw thread screwed in the above-mentioned female screwthread is cut. In a case of fitting the lens barrel 12 to the lensholder 24, it includes the steps of rotating the lens barrel 12 withrespect to the tubular portion 240 of the lens holder 24 around theoptical axis O to screw it along the direction of the optical axis Othereby accommodating the lens barrel 12 in the lens holder 24, and ofconnecting them to each other via an adhesive agent or the like.

In the manner which will later be described, by flowing an auto-focusing(AF) current through the focusing coil 26, it is possible topositionally adjust the lens holder 24 (the lens barrel 12) in thedirection of the optical axis O according to interaction between amagnetic field of the permanent magnet 28 and a magnetic field due tothe AF current flowing through the focusing coil 26.

In the manner which is described above, the auto-focusing lens holderdriving portion (the AF unit) 20 comprises the lens holder 24, thefocusing coil 26, the permanent magnet 28, the magnet holder 30, theupper leaf spring 32, the lower leaf spring 34, and the spacer 36.

Referring now to FIG. 3, the description will proceed to the imagestabilizer portion of the lens holder driving device 10 in more detail.

In the manner which is described above, the image stabilizer portion ofthe lens holder driving device 10 comprises the four suspension wires 16having the first end portion 161 fixed to the fixed member 13 at thefour corner portions thereof, and the image stabilizer coil (the drivingcoil) 18 disposed to face the permanent magnet 28 of the above-mentionedauto-focusing lens holder driving portion 20 (the lens holder movingportion (26; 28; 30)).

The four suspension wires 16 extend along the optical axis O andswingably support the auto-focusing lens holder driving portion 20 (thelens holder moving portion (26; 28; 30)) as a whole in the firstdirection (the fore-and-aft direction) X and the second direction (theleft-and-right direction) Y. The four suspension wires 16 have thesecond end portions 162 which are fixed to the upper end portion of theabove-mentioned auto-focusing lens holder driving portion 20 (the lensholder moving portion (26; 28; 30)).

More specifically, in the manner which is described above, the fourarc-shaped extending portions 328 of the upper leaf spring 32 have thefour wire fixing holes 328 a in which the second end portions 162 of thefour suspension wires 16 are inserted (charged), respectively (see, FIG.3). In the four wire fixing holes 328 a, the second end portions 162 ofthe four suspension wires 16 are inserted (charged) and are fixed bymeans of an adhesive agent, solder, or the like.

Although each arc-shaped extending portion 328 has an L-shape in theexample being illustrated, of course, it is not limited to this.

Two of the four suspension wires 16 are also used to feed to thefocusing coil 26.

In the manner which is described above, the permanent magnet 28comprises the four permanent magnet pieces 282 which are disposed so asto oppose to each other in the first direction (the fore-and-aftdirection) X and the second direction (the left-and-right direction) Y.

The image stabilizer portion of the lens holder driving device 10comprises the ring-shaped coil board 40 which is inserted between thefour permanent magnet pieces 282 and the base 14 and which is disposedso as to apart from them. The coil board 40 has, at four cornersthereof, four through holes 40 a through which the four suspension wires16 pass and in which the first end portions 161 are fixed. Theabove-mentioned image stabilizer coil (the driving coil) 18 for drivingthe lens holder moving portion (26; 28; 30) is formed on the coil board40.

In the manner which is described above, the combination of the base 14,the coil board 40, the image stabilizer coil (the driving coil) 18, andthe flexible printed circuit (FPC) 44 serves as the fixed member 13disposed apart from the auto-focusing coil holder driving portion 20(the lens holder moving portion (26; 28; 30)) in the direction of theoptical axis O.

Herein, in the four permanent magnet pieces 282, the permanent magnetpieces disposed with respect to the optical axis O at a front side, arear side, a left side, and a right side are called a front-sidepermanent magnet piece 282 f, a rear-side permanent magnet piece 282 r,a left-side permanent magnet piece 282 l, and a right-side permanentmagnet piece 282 r, respectively.

Referring to FIG. 4 also, on the coil board 40, four image stabilizercoil portions (driving coil portions) 18 f, 18 b, 18 l, and 18 r areformed as the image stabilizer coil (the driving coil) 18.

Disposed opposite to each other in the first direction (the fore-and-aftdirection) X, the two image stabilizer coil portions (the driving coilportions) 18 f and 18 b are for moving (swinging) the auto-focusing lensholder driving portion (the AF unit) 20 (the lens holder moving portion(26; 28; 30)) in the first direction (the fore-and-aft direction) X.Such two image stabilizer coil portions (the driving coil portions) 18 fand 18 b are collectively called a first direction actuator. Herein, theimage stabilizer coil portion 18 f disposed at a front side with respectto the optical axis O is called “a front-side image stabilizer coilportion” while the image stabilizer coil portion 18 b disposed at a backside with respect to the optical axis O is called “a back-side imagestabilizer coil portion”.

On the other hand, disposed opposite to each other in the seconddirection (the left-and-right direction) Y, the two image stabilizercoil portions (the driving coil portions) 18 l and 18 r are for moving(swinging) the auto-focusing lens holder driving portion (the AF unit)20 (the lens holder moving portion (26; 28; 30)) in the second direction(the left-and-right direction) Y. Such two image stabilizer coilportions (the driving coil portions) 18 l and 18 r are collectivelycalled a second direction actuator. Herein, the image stabilizer coilportion 18 l disposed at a left side with respect to the optical axis Ois called “a left-side image stabilizer coil portion” while the imagestabilizer coil portion 18 r disposed at a right side with respect tothe optical axis O is called “a right-side image stabilizer coilportion”.

As shown in FIG. 4, in the illustrated image stabilizer coil (thedriving coil) 18, each of the front-side image stabilizer coil portion18 f and the left-side image stabilizer coil portion 18 l is dividedinto two coil parts so as to separate at a center in a longitudinaldirection of the front-side permanent magnet piece 182 f and theleft-side permanent magnet piece 1821 opposite thereto, respectively.That is, the front-side image stabilizer coil portion 18 f comprises aleft-side coil part 18 f 1 and a right-side coil part 18 fr. Likewise,the left-side image stabilizer coil portion 18 l comprises a front-sidecoil part 18 lf and a back-side coil part 18 lb.

In other words, each of the front-side image stabilizer coil portion 18f and the left-side image stabilizer coil portion 18 r comprises twoloop portions while each of the back-side image stabilizer coil portion18 b and the right-side image stabilizer coil portion 18 r comprisesonly one loop portion.

In the manner which is described above, among the four image stabilizercoil portions (the driving coil portions) 18 f, 18 b, 18 l, and 18 r,each of two particular image stabilizer coil portions 18 f and 18 ldisposed in the first direction X and the second direction Y is dividedinto the two coil parts 18 f 1, 18 fr and 18 lf, 18 lb so as to separateit at the center of the longitudinal direction of the permanent magnetpieces 282 f and 2821 opposite thereto.

The four image stabilizer coil portions (the driving coil portions) 18f, 18 b, 18 l, and 18 r configured as described above in cooperationwith the permanent magnet 28 are for driving the auto-focusing lensholder driving portion (the AF unit) 20 (the lens holder moving portion(26; 28; 30)) as a whole in the X-axis direction (the first direction)and the Y-axis direction (the second direction). A combination of thefour image stabilizer coil portions (the driving coil portions) 18 f, 18b, 18 l, and 18 r and the permanent magnet 28 serves as a voice coilmotor (VCM).

In the manner which is described above, the illustrated image stabilizerportion of the lens holder driving device 10 stabilizes the blurryimages by moving the lens barrel 12 received in the auto-focusing lensholder driving portion (the AF unit) 20 (the lens holder moving portion(26; 28; 30)) itself in the first direction (the fore-and-aft direction)X and the second direction (the left-and-right direction) Y.Accordingly, the image stabilizer portion of the lens holder drivingdevice 10 is called an image stabilizer portion of “a barrel shiftmethod”.

Turning back to FIG. 3, the lens holder driving device 10 furthercomprises a shielding cover 42 for covering the auto-focusing lensholder driving portion (the AF unit) 20. The shielding cover 42comprises a rectangular tubular portion 422 for covering an outerperiphery of the auto-focusing lens holder driving portion (the AF unit)20 and a ring-shaped upper end portion 424 for covering an upper surfaceof the auto-focusing lens holder driving portion (the AF unit) 20. Theupper end portion 424 has a circular opening 424 a concentric with theoptical axis O.

The illustrated image stabilizer portion of the lens holder drivingdevice 10 further comprises a position detection arrangement 50 fordetecting a position of the auto-focusing lens holder driving portion(the AF unit) 20 (the lens holder moving portion (26; 28; 30)) withrespect to the base 14 (the fixed portion 13). The illustrated positiondetection arrangement 50 comprises a magnetic position detectionarrangement comprising two Hall elements 50 f and 501 mounted on thebase 14 (see, FIG. 11). The two Hall elements 50 f and 501 are disposedso as to oppose with a space to two of the four permanent magnet pieces282, respectively, in the manner which will later be described. As shownin FIG. 2, each Hall element 50 f and 501 is disposed so as to cross ina direction from the north pole to the south pole in the permanentmagnet piece 282.

In the example being illustrated, one Hall element 50 f is called afront-side Hall element because the Hall element 50 f is disposed at afront side in the first direction (the fore-and-aft direction) X withrespect to the optical axis O. Another Hall element 501 is called aleft-side Hall element because the Hall element 501 is disposed at aleft side in the second direction (the left-and-right direction) Y withrespect to the optical axis O.

The front-side Hall element 50 f is disposed on the base 14 at aposition where the front-side image stabilizer coil portion 18 f havingthe divided two coil parts 18 f 1 and 18 fr is separated into the twocoil parts 18 f 1 and 18 fr. Similarly, the left-side Hall element 501is disposed on the base 14 at a position where the left-side imagestabilizer coil portion 18 l having the divided two coil parts 18 lf and18 lb is separated into the two coil parts 18 lf and 18 lb.

In the manner which is described above, the two Hall elements 50 f and501 are disposed on the base 14 at the positions where particular twoimage stabilizer coil portions 18 f and 18 l having the divided two coilparts 18 f 1, 18 fr and 18 lf, 18 lb are separated into two coil parts18 f 1, 18 fr and 18 lf, 191 b.

The front-side Hall element 50 f detects a first position with amovement (a swing) in the first direction (the fore-and-aft direction) Xby detecting a magnetic force of the front-side permanent magnet piece282 f opposite thereto. The left-side Hall element 501 detects a secondposition with a movement (a swing) in the second direction (theleft-and-right direction) Y by detecting a magnetic force of theleft-side permanent magnet piece 2821 opposite thereto.

Referring to FIGS. 5 through 7, the description will proceed to arelationship between a related magnetic circuit and Hall elements foruse in a related lens holder driving device in order to facilitate theunderstanding of the lens holder driving device 10 according to thefirst exemplary embodiment of the present invention. The relationshipbetween the illustrated related magnetic circuit and the Hall elementsis similar in structure (relationship) to that illustrated in theabove-mentioned Patent Document 2. FIG. 5 is a perspective view showingthe relationship between the related magnetic circuit and the Hallelements, FIG. 6 is a vertical cross sectional view showing therelationship between the related magnetic circuit and the Hall elements,and FIG. 7 is a vertical cross sectional view shoring the relationshipbetween the related magnetic circuit and the Hall elements in a case ofdisplacing the AF unit 20 in the fore-and-aft direction X.

A difference between the related magnetic circuit and the magneticcircuit used in the lens holder driving device 10 according to thisexemplary embodiment is that any of four image stabilizer coil portions(driving coil portions) 18 f′, 18 b′, 18 l′, and 18 r′ constituting animage stabilizer coil (a driving coil) 18′ in the related magneticcircuit comprises no two loop ports. That is, in the related magneticcircuit, each of the four image stabilizer coil portions (the drivingcoil portions) 18 f, 18 b′, 18 l′, and 18 r′ comprises only one looppart.

As described above, each of the four permanent magnet pieces 282 f, 282b, 2821, and 282 r has the inner side polarized (magnetized) to thenorth pole and the outer side polarized (magnetized) to the south pole.Arrows B depicted in FIG. 5 indicate directions of magnetic fluxesgenerated by the permanent magnet pieces.

Referring now to FIG. 5, the description will be made as regardsoperation in a case of position adjusting the lens holder 24 (the lensbarrel 12) in the direction of the optical axis O by using the relatedmagnetic circuit.

By way of illustration, it will be assumed that the AF current is flowedthrough the focusing coil 26 counterclockwise. In this event, accordingto Fleming's right-hand rule, the focusing coil 26 is acted upon by anelectromagnetic force upwards. As a result, it is possible to move thelens holder 24 (the lens barrel 12) in the direction of the optical axisO upwards.

Conversely, by flowing the AF current through the focusing coil 26clockwise, it is possible to move the lens holder 24 (the lens barrel12) in the direction of the optical axis O downwards.

Referring now to FIGS. 5 to 7, the description will be made as regardsoperation in a case of moving the auto-focusing lens holder drivingportion (the AF unit) 20 (the lens holder moving portion (26; 28; 30))as a whole in the first direction (the fore-and-aft direction) X or thesecond direction (the left-and-right direction) Y by using the relatedmagnetic circuit.

First, the description will be made as regards operation in a case ofmoving the auto-focusing lens holder driving portion (the AF unit) 20(the lens holder moving portion (26; 28; 30)) as a whole in the firstdirection (the fore-and-aft direction) X backwards. In this event, asshown in FIG. 5, a first image stabilizing (IS) current flows throughthe front-side image stabilizer coil portion 18 f counterclockwise asdepicted at an arrow I_(IS1) and a second image stabilizing (IS) currentflows through the back-side image stabilizer coil portion 18 b′clockwise as depicted at an arrow I_(IS2).

In this event, according to Fleming's right-hand rule, the front-sideimage stabilizer coil portion 18 f′ is acted upon by an electromagneticforce forwards and the back-side image stabilizer coil portion 18 b′ isalso acted upon by an electromagnetic force forwards. However, inasmuchas there image stabilizer coil portions (the driving coil portions) 18f′ and 18 r′ are fixed to the base 14 (the fixed member 13), asreaction, the auto-focusing lens holder driving portion (the AF unit) 20(the lens holder moving portion (26; 28; 30)) as a whole is acted uponby an electromagnetic force backwards, as depicted at arrows F_(IS1) andF_(IS2) in FIG. 6. As a result, it is possible to move the auto-focusinglens holder driving portion (the AF unit) 20 (the lens holder movingportion (26; 28; 30)) as a whole backwards.

Conversely, by flowing the first IS current through the front-side imagestabilizer coil portion 18 f′ clockwise and by flowing the second IScurrent through the back-side image stabilizer coil portion 18 b′counterclockwise, it is possible to move the auto-focusing lens holderdriving portion (the AF unit) 20 (the lens holder moving portion (26;28; 30)) as a whole forwards.

On the other hand, by flowing a third IS current through the left-sideimage stabilizer coil portion 18 l′ counterclockwise and by flowing afourth IS current through the right-side image stabilizer coil portion18 r′ clockwise, it is possible to move the auto-focusing lens holderdriving portion (the AF unit) 20 (the lens holder moving portion (26;28; 30)) as a whole rightwards.

In addition, by flowing the third IS current through the left-side imagestabilizer coil portion 18 l′ clockwise and by flowing the fourth IScurrent through the right-side image stabilizer coil portion 18 r′counterclockwise, it is possible to move the auto-focusing lens holderdriving portion (the AF unit) 20 (the lens holder moving portion (26;28; 30)) as a whole leftwards.

In the manner which is described above, it is possible to stabilizeblurry images.

Referring now to FIGS. 8 through 10 in addition to FIGS. 5 through 7,the description will proceed to problems in the related lens holderdriving device using the related magnetic circuit in more details.

The description will be made as taking a case as an example where thefirst IS current flows through the front-side image stabilizer coilportion 18 f′ counterclockwise as depicted at the arrow I_(IS1) and thesecond IS current flows through the back-side image stabilizer coilportion 18 b′ clockwise as depicted at the arrow I_(IS2), as shown inFIG. 5, in order to move the auto-focusing lens holder driving portion(the AF unit) 20 (the lens holder moving portion (26; 28; 30)) as awhole backwards in the manner which is described above.

In this event, as shown in FIG. 7, it is understood that a magneticfield B₁₁ produced by the first IS current I_(IS1) flowing through thefront-side image stabilizer coil portion 18 f′ and the magnetic field Bproduced by the front-side permanent magnet piece 282 f are in phase. Itwill be assumed that magnetic flux density of the magnetic field B isindicated by a and magnetic flux density of the magnetic field B₁₁ isindicated by b. Accordingly, it is understood that the front-side Hallelement 50 f detects total magnetic flux density (a+b) obtained bysumming the magnetic flux density a of the magnetic field B and themagnetic flux density b of the magnetic field B₁₁.

It is herein noted that it is necessary that the magnetic flux density aof the magnetic field B and the total magnetic flux density (a+b) are inphase in order to detect a position of the auto-focusing lens holderdriving portion (the AF unit) 20 (the lens holder moving portion (26;28; 30)) by means of the front-side Hall element 50 f.

FIG. 8 is a view showing a frequency response of the front-side Hallelement 50 f in the related magnetic circuit. In FIG. 8, the horizontalaxis represents a frequency (Frequency) (Hz), the left-hand verticalaxis represents a gain (Gain) (dB), and the right-hand vertical axisrepresents a phase (Phase) (deg). In addition, in FIG. 8, a solid lineindicates a gain characteristic and an alternate long and short dashedline indicate a phase characteristic.

As is apparent from FIG. 8, the frequency response of the font-side Hallelement 50 f is divided into a region I, a region II, and a region III.The region I is a region having a band not higher than a primaryresonance frequency of the actuator and having low frequencies. Theregion II is a region having a band not lower than the primary resonancefrequency of the actuator and having middle frequencies. The region IIIis a region having a band not lower than the primary resonance frequencyof the actuator and having high frequencies.

FIGS. 9A, 9B, and 9C are views showing relationships between phases andmagnitudes among the magnetic flux density a of the magnetic field Bgenerated by the front-side permanent magnetic piece 282 f, the magneticflux density b of the magnetic field B₁₁ generated by the first IScurrent I_(IS1) flowing through the front-side image stabilizer coil 18f, and the total magnetic flux density (a+b) detected by the front-sideHall element 50 f in the region I, the region II, and the region III ofFIG. 8, respectively. FIG. 10 is a view tabulated for the relationshipsof FIGS. 9A-9C;

It is understood from FIGS. 9A-9C and 10 as follows.

In the band not higher than the primary resonance frequency of theregion I, a magnitude |a| of the magnetic flux density a of the magneticfield B is larger than a magnitude |b| of the magnetic flux density b ofthe magnetic field B₁₁ (|a|>|b|), and the magnetic flux density a of themagnetic field B, the magnetic flux density b of the magnetic field B₁₁,and the total magnetic flux density (a+b) are in phase. Accordingly, inthe region I, it is possible to detect the position of the auto-focusinglens holder driving portion (the AF unit) 20 (the lens holder movingportion (26; 28; 30)) by means of the front-side Hall element 50 f.

On the other hand, in a band not lower than primary resonance frequency,the magnetic flux density a of the magnetic field B and the magneticflux density b of the magnetic field B₁₁ are opposite phase becausemovement of the front-phase permanent magnet piece 282 f shifts withrespect to a phase of the first IS current I_(IS1) flowing through thefront-side image stabilizer coil portion 18 f by 180 degrees.

In the band not lower than the primary resonance frequency of the regionII, the magnetic flux density a of the magnetic field B and the totalmagnetic flux density (a+b) are in phase because the magnitude |a| ofthe magnetic flux density a of the magnetic field B is larger than amagnitude |b| of the magnetic flux density b of the magnetic field B₁₁(|a|>|b|). Accordingly, in the region II, it is possible to detect theposition of the auto-focusing lens holder driving portion (the AF unit)20 (the lens holder moving portion (26; 28; 30)) by means of thefront-side Hall element 50 f.

However, in the band not lower than the primary resonance frequency ofthe region III, it is understood that the magnitude |a| of the magneticflux density a of the magnetic field B is smaller than a magnitude |b|of the magnetic flux density b of the magnetic field B₁₁ (|a|<|b|).Therefore, the magnetic flux density a of the magnetic field B and thetotal magnetic flux density (a+b) are opposite phase. As a result, inthe region III, it is impossible to detect the position of theauto-focusing lens holder driving portion (the AF unit) 20 (the lensholder moving portion (26; 28; 30)) by means of the front-side Hallelement 50 f. That is, an output of Hall element has resonance.

Accordingly, when the Hall element is disposed between (in) the looppart of the coil, it is understood that it is impossible to detect theposition of the auto-focusing lens holder driving portion (the AF unit)20 (the lens holder moving portion (26; 28; 30)) in the region III whichis not lower than the primary resonance frequency. In other words, theHall elements 50 f and 501 are subjected to adverse effect caused by themagnetic fields generated by the currents flowing through the imagestabilizer coil portions (the driving coil portions) 18 f and 18 l′,respectively.

Referring now to FIGS. 11 through 14, the description will proceed to arelationship between the magnetic circuit according to this exemplaryembodiment and the Hall elements for use in the lens holder drivingdevice 10 according to the first exemplary embodiment of this invention.FIG. 11 is a perspective view showing the relationship between themagnetic circuit according to this exemplary embodiment and the Hallelements, FIG. 12 is a vertical cross sectional view showing therelationship between the magnetic circuit according to this exemplaryembodiment and the Hall elements, FIG. 13 is a vertical cross sectionalview shoring the relationship between the magnetic circuit according tothis exemplary embodiment and the Hall elements in a case of displacingthe AF unit 20 (the lens holder moving portion (26; 28; 30)) in thefore-and-aft direction X, and FIG. 14 is a cross sectional view taken online XIV-XIV of FIG. 13.

As described above, each of the four permanent magnet pieces 282 f, 282b, 2821, and 282 r has the inner side polarized (magnetized) to thenorth pole and the outer side polarized (magnetized) to the south pole.Arrows B depicted in FIG. 11 indicate directions of magnetic fluxesgenerated by the permanent magnet pieces.

Referring now to FIG. 11, the description will be made as regardsoperation in a case of position adjusting the lens holder 24 (the lensbarrel 12) in the direction of the optical axis O by using the magneticcircuit according to this exemplary embodiment.

By way of illustration, it will be assumed that the AF current is flowedthrough the focusing coil 26 counterclockwise. In this event, accordingto Fleming's right-hand rule, the focusing coil 26 is acted upon by anelectromagnetic force upwards. As a result, it is possible to move thelens holder 24 (the lens barrel 12) in the direction of the optical axisO upwards.

Conversely, by flowing the AF current through the focusing coil 26clockwise, it is possible to move the lens holder 24 (the lens barrel12) in the direction of the optical axis O downwards.

Referring now to FIGS. 11 to 14, the description will be made as regardsoperation in a case of moving the auto-focusing lens holder drivingportion (the AF unit) 20 (the lens holder moving portion (26; 28; 30) asa whole in the first direction (the fore-and-aft direction) X or thesecond direction (the left-and-right direction) Y by using the magneticcircuit according to this exemplary embodiment.

First, the description will be made as regards operation in a case ofmoving the auto-focusing lens holder driving portion (the AF unit) 20(the lens holder moving portion (26; 28; 30)) as a whole in the firstdirection (the fore-and-aft direction) X backwards. In this event, asshown in FIG. 11, a first image stabilizing (IS) current flows througheach of the tow coil parts 18 fl and 18 fr of the front-side imagestabilizer coil portion 18 f counterclockwise as depicted at an arrowI_(IS1) and a second image stabilizing (IS) current flows through theback-side image stabilizer coil portion 18 b clockwise as depicted at anarrow I_(IS2).

In this event, according to Fleming's right-hand rule, the front-sideimage stabilizer coil portion 18 f is acted upon by an electromagneticforce forwards and the back-side image stabilizer coil portion 18 b isalso acted upon by an electromagnetic force forwards. However, inasmuchas there image stabilizer coil portions (the driving coil portions) 18 fand 18 r are fixed to the fixed member 13, as reaction, theauto-focusing lens holder driving portion (the AF unit) 20 (the lensholder moving portion (26; 28; 30) as a whole is acted upon by anelectromagnetic force backwards, as depicted at arrows F_(IS1) andF_(IS2) in FIG. 12. As a result, it is possible to move theauto-focusing lens holder driving portion (the AF unit) 20 (the lensholder moving portion (26; 28; 30) as a whole backwards.

Conversely, by flowing the first IS current through each of the two coilparts 18 f 1 and 18 fr of the front-side image stabilizer coil portion18 f clockwise and by flowing the second IS current through theback-side image stabilizer coil portion 18 b counterclockwise, it ispossible to move the auto-focusing lens holder driving portion (the AFunit) 20 (the lens holder moving portion (26; 28; 30)) as a wholeforwards.

On the other hand, by flowing a third IS current through each of the twocoil parts 18 lf and 18 lb of the left-side image stabilizer coilportion 18 l counterclockwise and by flowing a fourth IS current throughthe right-side image stabilizer coil portion 18 r clockwise, it ispossible to move the auto-focusing lens holder driving portion (the AFunit) 20 (the lens holder moving portion (26; 28; 30) as a wholerightwards.

In addition, by flowing the third IS current through each of the twocoil parts 18 lf and 18 lr of the left-side image stabilizer coilportion 18 l clockwise and by flowing the fourth IS current through theright-side image stabilizer coil portion 18 r counterclockwise, it ispossible to move the auto-focusing lens holder driving portion (the AFunit) 20 (the lens holder moving portion (26; 28; 30)) as a wholeleftwards.

In the manner which is described above, it is possible to stabilizeblurry images in the camera.

Referring now to FIGS. 15 through 17 in addition to FIGS. 11 through 14,the description will proceed to advantages in the lens holder drivingdevice 10 using the magnetic circuit according to this exemplaryembodiment in more details.

The description will be made as taking a case as an example where thefirst IS current flows through each of the two coil parts 18 f 1 and 18fr of the front-side image stabilizer coil portion 18 f counterclockwiseas depicted at the arrow I_(IS1) and the second IS current flows throughthe back-side image stabilizer coil portion 18 b clockwise as depictedat the arrow I_(IS2), as shown in FIG. 11, in order to move theauto-focusing lens holder driving portion (the AF unit) 20 (the lensholder moving portion (26; 28; 30)) as a whole backwards in the mannerwhich is described above.

In this event, as shown in FIGS. 13 and 14, it is understood that amagnetic field B₁₁ produced by the first IS current I_(IS1) flowingthrough the front-side image stabilizer coil portion 18 f and themagnetic field B produced by the front-side permanent magnet piece 282 fare opposite phase. It will be assumed that magnetic flux density of themagnetic field B is indicated by a and magnetic flux density of themagnetic field B₁₁ is indicated by b. Accordingly, it is understood thatthe front-side Hall element 50 f detects total magnetic flux density(a+b) obtained by summing the magnetic flux density a of the magneticfield B and the magnetic flux density b of the magnetic field B₁₁.

It is herein noted that it is necessary that the magnetic flux density aof the magnetic field B and the total magnetic flux density (a+b) are inphase in order to detect a position of the auto-focusing lens holderdriving portion (the AF unit) 20 (the lens holder moving portion (26;28; 30)) by means of the front-side Hall element 50 f.

FIG. 15 is a view showing a frequency response of the front-side Hallelement 50 f in the magnetic circuit according to this exemplaryembodiment. In FIG. 15, the horizontal axis represents a frequency(Frequency) (Hz), the left-hand vertical axis represents a gain (Gain)(dB), and the right-hand vertical axis represents a phase (Phase) (deg).In addition, in FIG. 15, a solid line indicates a gain characteristicand an alternate long and short dashed line indicate a phasecharacteristic.

As is apparent from FIG. 15, the frequency response of the font-sideHall element 50 f is divided into a region I, a region II, and a regionIII. The region I is a region having a band not higher than a primaryresonance frequency of the actuator and having low frequencies. Theregion II is a region having a band not lower than the primary resonancefrequency of the actuator and having middle frequencies. The region IIIis a region having a band not lower than the primary resonance frequencyof the actuator and having high frequencies.

FIGS. 16A, 16B, and 16C are views showing relationships between phasesand magnitudes among the magnetic flux density a of the magnetic field Bgenerated by the front-side permanent magnetic piece 282 f, the magneticflux density b of the magnetic field B₁₁ generated by the first IScurrent I_(IS1) flowing through the front-side image stabilizer coil 18f, and the total magnetic flux density (a+b) detected by the front-sideHall element 50 f in the region I, the region II, and the region III ofFIG. 15, respectively. FIG. 17 is a view tabulated for the relationshipsof FIGS. 16A-160;

It is understood from FIGS. 16A-160 and 17 as follows.

In the band not higher than the primary resonance frequency of theregion I, a magnitude |a| of the magnetic flux density a of the magneticfield B is larger than a magnitude |b| of the magnetic flux density b ofthe magnetic field B₁₁ (0 a 1>|b|), and the magnetic flux density a ofthe magnetic field B and the total magnetic flux density (a+b) are inphase although the magnetic flux density a of the magnetic field B andthe magnetic flux density b of the magnetic field B₁₁ are oppositephase. Accordingly, in the region I, it is possible to detect theposition of the auto-focusing lens holder driving portion (the AF unit)20 (the lens holder moving portion (26; 28; 30)) by means of thefront-side Hall element 50 f.

On the other hand, in a band not lower than primary resonance frequency,the magnetic flux density a of the magnetic field B and the magneticflux density b of the magnetic field B₁₁ are in phase because movementof the front-phase permanent magnet piece 282 f is in phase with thefirst IS current I_(IS1) flowing through the front-side image stabilizercoil portion 18 f.

In the band not lower than the primary resonance frequency of the regionII, the magnetic flux density a of the magnetic field B and the totalmagnetic flux density (a+b) are in phase because the magnitude |a| ofthe magnetic flux density a of the magnetic field B is larger than amagnitude |b| of the magnetic flux density b of the magnetic field B₁₁(|a|>|b|). Accordingly, in the region II, it is possible to detect theposition of the auto-focusing lens holder driving portion (the AF unit)20 (the lens holder moving portion (26; 28; 30)) by means of thefront-side Hall element 50 f.

On the other hand, in the band not lower than the primary resonancefrequency of the region III, it is understood that the magnitude |a| ofthe magnetic flux density a of the magnetic field B is smaller than amagnitude |b| of the magnetic flux density b of the magnetic field B₁₁(|a|<|b|). However, inasmuch as the magnetic flux density b of themagnetic field B and the magnetic flux density b of the magnetic fieldB₁₁ are in phase, the magnetic flux density a of the magnetic field Band the total magnetic flux density (a+b) are also in phase. As aresult, in also the region III, it is possible to detect the position ofthe auto-focusing lens holder driving portion (the AF unit) 20 (the lensholder moving portion (26; 28; 30)) by means of the front-side Hallelement 50 f. That is, resonance does not occur in an output of Hallelement.

Accordingly, when the Hall element is disposed between the two loopparts of the coil, it is understood that it is possible to detect theposition of the auto-focusing lens holder driving portion (the AF unit)20 (the lens holder moving portion (26; 28; 30)) in all of frequencyranges. In other words, the Hall elements 50 f and 501 can avoid tosubject to adverse effect caused by the magnetic fields generated by thecurrents flowing through the image stabilizer coil portions (the drivingcoil portions) 18 f and 18 l, respectively.

FIG. 18 is a cross sectional view showing a relationship of a placementamong one permanent magnet piece 282 of the permanent magnet 28, thefocusing coil 26 disposed around it, and the image stabilizer coilportion 18 in the magnetic circuit illustrated in FIG. 11.

It is understood that a height of the permanent magnet piece 281 ishigher than a height of the focusing coil 26. It is therefore possibleto make a stoke larger in a case of position adjusting the lens holder24 (the lens barrel 12) in the direction of the optical axis O.

In addition, the permanent magnet piece 282 and the image stabilizercoil (the driving coil) 18 are disposed so that edges of the permanentmagnet piece 282 in the radial direction are laid in a coil sectionalwidth of the image stabilizer coil portion 18 in the radial direction.It is therefore possible to heighten sensitivity of a driving force formoving the auto-focusing lens holder driving portion (the AF unit) 20(the lens holder moving portion (26; 28; 30)) as a whole in a directionorthogonal to the optical axis O.

Incidentally, there is in danger that the four suspension wires 16 maybe fracture in the lens holder driving device 10 having such a structurebecause the four suspension wires 16 are subjected to force in adirection to expand caused by a drop impact or the like. On thisaccount, the lens holder driving device 10 according to the firstexemplary embodiment comprises a fracture preventing member forpreventing the four suspension wires 16 from fracturing in the mannerwhich will be presently described.

Referring to FIGS. 19 and 20, the description will proceed to thefracture preventing member according to this exemplary embodiment indetail. FIG. 19 is a partial perspective view enlargedly showing a partfixing the second end portion 162 of the suspension wire 16 to the upperleaf spring 32, FIG. 20 is a partial cross sectional view of the fixedpart.

In the manner which is described above, the upper leaf spring 32comprises the four arc-shaped extending portions 328 (only onearc-shaped extending portion 328 is shown in FIG. 19) for extending atthe four corners of the upper outer end portion 324 in the radialdirection outwards. The four arc-shaped extending portions 328 have, attip portions thereof, four wire fixing holes 328 a (see, FIG. 3) inwhich the second end portions 162 of the four suspension wires 16 areinserted (fitted), respectively. The second end portions 162 of the foursuspension wires 16 are inserted in the four wire fixing holes 328 a tobe fixed to the four arc-shaped extending portions 328 by means ofsolder 60 or adhesive agent (not shown).

Accordingly, the four arc-shaped extending portions 328 serve as a wirefixing portion for fixing the second end portions 162 of the foursuspension wires 16.

In the lens holder driving device 10 having such a structure, althoughthe auto-focusing lens holder driving portion (the AF unit) 20 (the lensholder moving portion (26; 28; 30)) is subjected to the force in thedirection to apart from the base 14 (the fixed member 13) due to a dropimpact or the like, the auto-focusing lens holder driving section (theAF unit) 20 (the lens holder moving portion (26; 28; 30)) moves upwardwith the four arc-shaped extending portions 328 elastically deformed ina state where the second end portions 162 of the four suspension wire 16are fixed to the four arc-shaped extending portions 328.

As a result, it is possible to prevent the four suspension wires 16 fromfracturing. Accordingly, the four arc-shaped extending portions 328 actsas the facture preventing member for preventing the four suspensionwires 16 from fracturing.

On the other hand, as shown in FIG. 19, the magnet holder 30 comprisesfour upper stoppers 308 (only one upper stopper 308 is shown in FIG. 19)which project at the four corners of the upper ring-shaped end portion304 upwards. Each upper stopper 308 projects from an opening 32 a formedin the upper leaf spring 32 between the upper outer end portion 324 andthe each arc-shaped extending portion 328.

In other words, the four upper stoppers 308 project from the magnetholder 30 toward an inner wall surface of the shielding cover 42.

By the four upper stoppers 308, movement of the auto-focusing lensholder driving portion (the AF unit) 20 (the lens holder moving portion(26; 28; 30)) upwards is limited. In other words, when auto-focusinglens holder driving section (the AF unit) 20 (the lens holder movingportion (26; 28; 30)) moves upwards, the four upper stoppers 308 of themagnet holder 30 hits to the inner wall surface of the upper end portion424 of the shielding cover 42 although the four arc-shaped extendingportions 328 become elastically deformed before the four arc-shapedextending portions 328 buckle or before the four suspension wires 16 aresubjected to a fracturing force.

That is, the four upper stoppers 308 serve as a fracture preventionsupporting member for supporting prevention of fracture in the foursuspension wires 16.

As shown in FIG. 2, there is little clearance (gap) between the fixedmember 13 and the auto-focusing lens holder driving portion (the AFunit) 20 (the lens holder moving portion (26; 28; 30)). Accordingly,although the auto-focusing lens holder driving portion (the AF unit) 20(the lens holder moving portion (26; 28; 30)) is subjected to a force ina direction to get near the fixed member 13 due to a drop impact or thelike, the four suspension wires 16 do not buckle because theauto-focusing lens holder driving portion (the AF unit) 20 (the lensholder moving portion (26; 28; 30)) immediately hits to an upper surfaceof the fixed member 13.

Referring to FIG. 21 in addition to FIGS. 2 to 4, the description willproceed to the flexible printed circuit (FPC) 44 disposed between thebase 41 and the coil board 40 and a method of mounting it. FIG. 21 is aperspective view showing an assembly of the coil board 40 and theflexible printed circuit (FPC) 44 seen from a rear side;

As shown in FIG. 3, the base 14 has four positioning protrusions 142which project upwards on diagonal lines in vicinity of the circularopening 14 a in the radial direction outwards. On the other hand, asshown in FIG. 4, the coil board 40 has four positioning hole portions 40b in which the four positioning protrusions 142 are charged,respectively. As shown in FIG. 21, the flexible printed circuit (FPC) 44also has four positioning hole portions 44 a at positions correspondingto the four positioning hole portions 40 b. Accordingly, the fourpositioning protrusions 142 of the base 14 are charged in the fourpositioning hole portions 40 b of the coil board 40 via the fourpositioning hole portions 44 a of the flexible printed circuit (FPC) 44.

As shown in FIG. 21, the flexible printed circuit (FPC) 44 has a rearsurface on which the two Hall elements 50 f and 501 are mounted. On theother hand, as shown in FIG. 2, the base 14 has concave portions 14 b inwhich the two Hall elements 50 f and 501 are fitted.

As shown in FIG. 4, on the coil board 40, six lands 18 a for supplyingelectric currents to the four image stabilizer coil portions (thedriving coil portions) 18 f, 18 b, 18 l, and 18 r are formed along thecircular opening 40 a bored at a central portion thereof. On the otherhand, as shown in FIG. 21, on the flexible printed circuit (FPC) 44, sixnotch portions 44 b are formed at positions corresponding to the sixlands 18 a. Accordingly, by mounting solder pastes on the six notchportions 44 b and by carrying out solder reflow, it is possible toelectrically connect internal wiring (not shown) of the flexible printedcircuit (FPC) 44 with the six lands 18 a of the coil board 44.

In the manner which is described above, the first end portions 161 ofthe four suspension wires 16 pass through the four through holes 40 a ofthe coil board 40 and are fixed to the coil board 40.

As shown in FIG. 4, on the coil board 40, four lands are formed aroundthe four through holes 40 a, respectively. Among the four lands formedaround the through holes 40 a, two lands (right-back and left-front inthe example of FIG. 4) are electrically connected to the inner wiring(not shown) of the flexible printed circuit (FPC) 44 by means of solder.Accordingly, among the four suspension wires 16, the first end portions161 of the two suspension wires 16 are fixed to the coil board 40 at theabove-mentioned two lands by means of the above-mentioned solder and areelectrically connected to the flexible printed circuit (FPC) 44. On theother hand, the first end portions 161 of remaining two suspension wires16 are fixed to the coil board 40 at remaining two lands by means ofsolder or adhesive agent but are electrically insulated to the internalwiring (not shown) of the flexible printed circuit (FPC) 44.

As shown in FIG. 21, the flexible printed circuit (FPC) 44 has a rearsurface on which a control portion 46 is mounted. The control portion 46controls the AF current flowing through the focusing coil 16 andcontrols the first through fourth IS currents flowing through the fourimage stabilizer coil portions (the driving coil portions) 18 f, 18 b,18 l, and 18 r so as to compensate wobbling detected based on twodirectional gyro sensors (not shown) on the basis of position detectedsignals detected by the two Hall elements 50 f and 501.

Referring to FIGS. 22 and 23, the description will proceed to a methodfor feeding to the focusing coil 26. FIG. 22 is a plan view showing astate where the shielding cover 42 is omitted from the lens holderdriving device 10. FIG. 23 is a partial enlarged perspective viewenlargedly showing a tied-up part of an end portion of a wire composedof the focusing coil 26.

As shown in FIG. 22, lens holder 24 has, at an upper end thereof, firstand second projecting portions 241 and 242 which project in a direction(outwards in the radial direction) to apart from each other in theleft-and-right direction Y. In the example being illustrated, the firstprojecting portion 241 is also called a right-side projecting portionbecause it projects to right side while the second projecting portion242 is also called a left-side projecting portion because it projects toleft side.

On the other hand, the wire composed of the focusing coil 26 has firstand second end portions 261 and 262. As shown in FIG. 23, the first endportion 261 of the wire of the focusing coil 26 is tied up to the firstprojecting portion (the right-side projecting portion) 241 of the lensholder 24. Similarly, the second end portion 262 of the wire of thefocusing coil 26 is tied up to the second projecting portion (theleft-side projecting portion) 242 of the lens holder 24. Accordingly,the first and second end portions 261 and 262 are also called first andsecond tied-up parts, respectively.

On the other hand, as shown in FIG. 22, the first leaf spring (the upperleaf spring) 32 comprises first and second leaf spring pieces 32-1 and32-2 which are electrically insulated from each other. The first andsecond leaf spring pieces 32-1 and 32-2 have rotational symmetry shapeswith respect to the optical axis O of the lens as a center. The firstleaf spring piece 32-1 is disposed, at the first end (the upper end) ofthe magnet holder 30, substantially back side and right side while thesecond leaf spring piece 32-2 is disposed, at the first end (the upperend) of the magnet holder 30, substantially front side and left side.

The upper inner end portion 322 of the first leaf spring piece 32-1disposed at the right side has a first U-shaped terminal portion 322-1projecting rightwards (outwards in the radial direction) at a positioncorresponding to the first projecting portion (the right-side projectingportion) 241 of the lens holder 24. Likewise, the upper inner endportion 322 of the second leaf spring piece 32-2 disposed at theleft-side has a second U-shaped terminal portion 322-2 projectingleftwards (outwards in the radial direction) at a position correspondingto the second projecting portion (the left-side projecting portion) 242of the lens holder 24. The first U-shaped terminal portion 322-1 is alsocalled a right-side U-shaped terminal portion while the second U-shapedterminal portion 322-2 is also called a left-side U-shaped terminalportion.

The first U-shaped terminal portion (the right-side U-shaped terminalportion) 322-1 is electrically connected to the first end portion (thefirst tied-up part) 261 of the focusing coil 26 by means of solder (notshown) at the first projecting portion (the right-side projectingportion) 241 of the lens holder 24. Similarly, the second U-shapedterminal portion (the left-side U-shaped terminal portion) 322-2 iselectrically connected to the second end portion (the second tied-uppart) 262 of the focusing coil 26 by means of solder (not shown) at thesecond projecting portion (the left-side projecting portion) 242 of thelens holder 24.

In addition, in the manner which is described above, among the foursuspension wires 16, the second end portions 162 of the two suspensionwires 16 (right-back and left-front in the example of FIG. 22) areconnected to the arc-shaped extending portions 328 through the wirefixing holes 328 a by means of solder 60. The second end portions 162 ofremaining two suspension wires 16 (left-back and right-front in theexample of FIG. 22) are fixed to the arc-shaped extending portions 328through the wire fixing holes 328 a by means of adhesive agent 62.Solder may be used in lieu of the adhesive agent 62.

Furthermore, in the manner which is described above, among the foursuspension wires 16, the first end portions 161 of the two suspensionwires 16 (right-back and left-front in the example of FIG. 22) are fixedto the lands of the coil board 44 via the through holes 40 a by means ofsolder and are electrically connected to the flexible printed circuit(FPC) 44. The first end portions 161 of the remaining two suspensionwires 16 (left-back and right-front in the example of FIG. 22) areconnected to the lands of the coil board 40 via the through holes 40 aby means of solder or adhesive agent but are electrically insulated fromthe flexible printed circuit (FPC) 44.

Accordingly, the flexible printed circuit (FPC) 44 is electricallyconnected to the first end portion (the first tied-up part) 261 of thefocusing coil 26 via the suspension wire 16 of the right-back, the firstleaf spring piece 32-1 of the first leaf spring (the upper leaf spring)32, and the first U-shaped terminal portion (the right-side U-shapedterminal portion) 322-1. Similarly, the flexible printed circuit (FPC)44 is electrically connected to the second end portion (the secondtied-up part) 262 of the focusing coil 26 via the suspension wire 16 ofthe left-front, the second leaf spring piece 32-2 of the first leafspring (the upper leaf spring) 32, and the second U-shaped terminalportion (the left-side U-shaped terminal portion) 322-2.

In the manner which is described above, feeding to the focusing coil 26is carried out from the flexible printed circuit (FPC) 44 via the twosuspension wires 16 and the first leaf spring 32.

New, the description will proceed to a method of assembling the lensholder driving device 10.

First, the auto-focusing lens holder driving portion (the AF unit) 20 ismanufactured by assembling the lens holder 24, the focusing coil 26, thepermanent magnet 28, the magnet holder 30, the upper leaf spring 32, thelower leaf spring 34, and the spacer 36.

On the other hand, an assembly consisting of the coil board 40 and theflexible printed circuit (FPC) 44, as shown in FIG. 21, is manufacturedby the above-mentioned solder reflow. The assembly is mounted on thebase 14 provided the side of the first terminal portions 161 of the foursuspension wires 16.

Subsequently, the above-mentioned auto-focusing lens holder drivingportion (the AF unit) 20 is mounted on the base 14 via theabove-mentioned assembly and the second end portions 162 of the foursuspension wires 14 are fixed to the arc-shaped extending portions 328via the wire fixing holes 328 a by means of the solder 60 or theadhesive agent 62.

The first and second U-shaped terminal portions 322-1 and 322-2 of thefirst leaf spring (the upper leaf spring) 32 are connected to the firstand second end portions 261 and 261 of the focusing coil 26.

Lastly, the shielding cover 42 is put so as to cover the auto-focusinglens holder driving portion (the AF unit) 20 and a lower end of theshielding cover 42 is fixed to the base 14.

As such a manner, it is possible to easily assemble the lens holderdriving device 10.

The lens holder driving device 10 assembled in such a manner has a sizeof 11 mm×11 mm×4.2 mm.

Referring to FIGS. 24 through 27, the description will proceed to amethod of mounting four damper compounds 65 and positioning thereof thatis for suppressing undesired resonance in the direction O of the opticalaxis O of the auto-focusing lens holder driving portion (the AF unit) 20(the lens holder moving portion (26; 28; 30)) in the lens holder drivingdevice 10.

FIG. 24 is a fragmentary vertical sectional view showing a state wherethe shielding cover 42 is omitted from the lens holder driving device10. FIG. 25 is a fragmentary perspective view of the lens holder drivingdevice 10 seen from a slanting above. FIG. 26 is a fragmentary sectionalview of the lens holder driving device 10 in a case without any dampercompound 65. FIG. 27 is a fragmentary sectional view of the lens holderdriving device 10 in a case with the four damper compounds 65.

In the example being illustrated, the four damper compounds 65 aredisposed between the magnet holder 30 and the first leaf spring 32serving as the elastic member so as to enclose the four suspension wires16. More specifically, the magnet holder 30 (the lens holder movingportion (26; 28; 30)) comprises four extending portions 310, atpositions in the vicinity of the four wire fixing portions 328,extending at four corners of the magnet holder 30 (the lens holdermoving portion (26; 28; 30)) in the radial direction outwards so as toenclose the four suspension wires 16 with spaces. The four dampercompounds 65 are disposed between the four extending portions 310 andthe four wire fixing portions 328 so as to enclose the four suspensionwires 16, respectively. The four damper compounds 65 are easily applied,by using a dispenser (not shown), between the four extending portions310 and the four wire fixing portions 328, as shown in FIG. 27.

In the example being illustrated, as each damper compounds 65, anultraviolet cure silicone gel having viscosity of 90 Pa·s is used thatis sold by a product name of TB3168E made in ThreeBond Co., Ltd.

Accordingly, after the four damper compounds 65 are applied to gapsbetween the four extending portions 310 of the magnet holder 30 and thefour wire fixing portions 328 in the manner which is described above,the four damper compounds 65 are cured by irradiating the four dampercompounds 65 with ultraviolet.

Referring to FIGS. 28 and 29, the description will proceed to frequencyresponses in a case where the four damper compounds 65 are absent (priorart example) and in a case where the four damper compounds 65 arepresent (the first exemplary embodiment). FIG. 28 is a view showing afrequency response of the auto-focusing lens driving portion (the AFunit) 20 of a conventional lens holder device without the four dampercompounds 65 in directions (X/Y) perpendicular to the optical axis Owhile FIG. 29 is a view showing a frequency response of theauto-focusing lens driving portion (AF unit) 20 of the lens holderdevice 10 according to the first exemplary embodiment of the presentinvention with the four damper compounds 65 in directions (X/Y)perpendicular to the optical axis O. In each of FIGS. 28 and 29, theabscissa presents a frequency [Hz] while the ordinate represents a gain[dB].

As is apparent from FIG. 28, in the conventional lens holder drivingdevice without the damper compounds 65, it is understood that undesiredresonance (a higher resonance mode) of the auto-focusing lens holderdriving portion (the AF unit) 20 is generated at frequencies of about400 Hz.

In contrast with this, as is apparent from FIG. 29, in the lens holderdriving device 10 according to the first exemplary embodiment with thefour damper compounds 65, it is understood that generation of suchundesired resonance (the higher resonance mode) is suppressed.

Accordingly, the lens holder driving device 10 according to the firstexemplary embodiment can carry out a stable control operation forstabilizing blurred images.

In addition, inasmuch as the four damper compounds 65 are disposed so asto support the auto-focusing lens holder driving portion (the AF unit)20 (the lens holder moving portion (26; 28; 30)) serving as a movablepart at a side for stabilizing blurred images, it also has an effectwhich can relief impact to the auto-focusing lens holder driving portion(the AF unit) 20 (the lens holder moving portion (26; 28; 30)) on a dropof the lens holder driving device 10.

The above-mentioned lens holder driving device 10 according to the firstexemplary embodiment of the present invention has effects which will bepresently described.

First, it is possible for the two Hall elements 50 f and 501 to avoid adetrimental effect caused by the magnetic field generated by the currentflowing through the specific two image stabilizer coil portions (thedriving coil portions) 18 f and 18 l because the two Hall elements 50 fand 501 are disposed on the base 14 at the positions where the specifictwo image stabilizer coil portions (the driving coil portions) 18 f and18 l are separated into the respective two coil parts 18 f 1, 18 fr and18 lf, 18 lb.

Secondly, it is possible to prevent the four suspension wires 15 fromfracturing and to heighten impact resistance of the lens holder drivingdevice 10 because the lens holder driving device comprises fracturepreventing member 328.

Thirdly, it is possible to electrically connect the inner wiring of theflexible printed circuit (FPC) 44 with the plurality of lands 18 a ofthe coil board 40 by means of solder reflow because the notch portions44 b are formed to the flexible printed circuit (FPC) 44 at thepositions corresponding to the plurality of lands 18 a formed on thecoil board 40.

Fourthly, it is possible to make the stoke in the case of positionadjusting the lens holder 24 (the lens barrel 12) in the direction ofthe optical axis O larger because the height of the focusing coil 26 islower than the height of the permanent magnet piece 282.

Fifthly, it is possible to enhance sensitivity of the driving force formoving the auto-focusing lens holder driving portion (the AF unit) 20(the lens holder moving portion (26; 28; 30)) as a whole in thedirection orthogonal to the optical axis O because the permanent magnetpieces 282 and the image stabilizer coil (the driving coil) 18 aredisposed so that the edges of the permanent magnet pieces in the radialdirection are laid in the coil sectional width of the image stabilizercoil (the driving coil) 18 in the radial direction.

Sixthly, it is possible to suppress undesired resonance of theauto-focusing lens holder driving portion (the AF unit) 20 (the lensholder moving portion (26; 28; 30)) and it is possible to carry out astable operation because the damper compounds 65 are disposed betweenthe magnet holder 30 and the elastic member 32 so as to enclose thesuspension wires 16.

Seventhly, it possible to prevent the damper compounds 65 from moving,rupturing, and degenerating on dropping/vibrating because each dampercompound 65 is disposed between the extending portion 310 of the magnetholder 30 and the wire fixing portion 328 of the first leaf spring 32 soas to enclose each suspension wire 16.

Eighthly, it is possible to easily apply a proper amount of the dampercompound 65 because the extending portion 310 is provided at theposition in the vicinity of the wire fixing portion 328 so as to encloseeach suspension wire 16 with a space.

Modified Examples

Now, the description will proceed to modified examples of the lensholder driving device 10 according to the first exemplary embodiment.

Although the four damper compounds 65 are provided at the four cornersof the magnet holder 30 (the lens holder moving portion (26; 28; 30)) inthe above-mentioned lens holder driving device 10 according to the firstexemplary embodiment, the number of the damper compounds 65 andconfiguration thereof are not important in this invention, it istherefore important that the damper compound 65 is disposed between thelens holder 30 (the lens holder moving portion (26; 28; 30)) and theelastic member 32 so as to enclose at least one suspension wire 16.

By way of illustration, one damper compound 65 may be provided at onlyone location as the lens holder driving device 10 according to a firstmodified example in the manner as illustrated in FIG. 30. In addition,two damper compounds 65 may be provided at two locations as the lensholder driving device 10 according to a second modified example in themanner as illustrated in FIG. 31.

In the manner which is described above, by proving one or plural dampercompounds 65 at one or plural locations as well, effects similar tothose of the above-mentioned first exemplary embodiment are obtained.

Although the ultraviolet cure silicone gel is used as the dampercompound 65 in the above-mentioned lens holder driving device 10according to the first exemplary embodiment, material of the dampercompound 65 is not limited thereto, and may use any material having adamper effect.

Referring to FIGS. 32 and 33, the description will proceed to a cameramodule 70 comprising the above-mentioned lens holder driving device 10.FIG. 32 is an external perspective view of the camera module 70, andFIG. 33 is an exploded perspective view showing the camera module 70.

The illustrated camera module 70 comprises the lens barrel 12 mounted(held) in the lens holder 24, the sensor board 72 on which the imagepickup device (sensor) 76 is mounted, and a holding member 74 which isdisposed between the sensor board 72 and the base 14 and which isholding an infrared-cut filter 78 in addition to the lens holder drivingdevice 10.

FIG. 34 is a perspective view showing appearance of a camera-equippedmobile terminal 80 on which the camera module 70 is mounted. Theillustrated camera-equipped mobile terminal 80 is a camera-equippedcellular mobile phone and shows a folded state. The camera module 70 ismounted at a predetermined potion of the camera-equipped mobile terminal80. With this structure, a user can shoot using the camera-equippedmobile terminal 80.

Although this example shows by taking as an example in a case of thecamera-equipped cellular mobile phone as the camera-equipped mobileterminal 80, the camera-equipped mobile terminal may be a smart phone, anotebook personal computer, a tablet-type personal computer, amobile-type game machine, a Web camera, and a vehicle-mounted camera.

Second Exemplary Embodiment

Referring to FIGS. 35 through 37, the description will proceed to a lensholder driving device 10A according to a second exemplary embodiment ofthe present invention. FIG. 35 is an external perspective view of thelens holder driving device 10A. FIG. 36 is a partial vertical crosssectional view of the lens holder driving device 10A. FIG. 37 is anexploded perspective view of the lens holder driving device 10A.

Herein, in the manner shown in FIGS. 35 to 37, an orthogonal coordinatesystem (X, Y, Z) is used. In a state illustrated in FIGS. 35 to 37, inthe orthogonal coordinate system (X, Y, X), an X-axis direction is afore-and-aft direction (a depth direction), a Y-axis direction is aleft-and-right direction (a width direction), and a Z-axis direction isan up-and-down direction (a height direction). In addition, in theexample being illustrated in FIGS. 35 to 37, the up-and-down direction Zis a direction of an optical axis O of a lens. In the second exemplaryembodiment, the X-axis direction (the fore-and-aft direction) is calleda first direction while the Y-axis direction (the left-and-rightdirection) is called in a second direction.

However, in an actual use situation, the direction of the optical axisO, namely, the Z-axis direction becomes a fore-and-aft direction. Inother words, an upper direction of the Z-axis becomes a front directionwhile a lower direction of the Z-axis becomes a rear direction.

The illustrated lens holder driving device 10A is similar in structureand operation to the above-mentioned lens holder driving device 10according to the first exemplary embodiment except that locations(positions) where the damper compounds 65 are different from in themanner which will later be described and a shape (structure) of theauto-focusing lens holder driving portion (the AF unit) (the lens holdermoving portion) is different from in the manner which will later bedescribed. The auto-focusing lens holder driving portion (the AF unit)is therefore depicted at 20A. The same reference signs are attached tothose having the same functions of the components of the lens holderdriving device 10 according to the first exemplary embodiment, and thedescription thereof is omitted for the sake of simplification of thedescription. Hereafter, only differences will be described.

The auto-focusing lens holder driving portion (the AF unit) 20A issimilar in structure and operation to the auto-focusing lens holderdriving portion (the AF unit) 20 according to the first exemplaryembodiment except that a shape (structure) of the magnet holder isdifferent from in the manner which will later be described. The magnetholder is therefore depicted at 30A.

FIG. 38 is a partial perspective view enlargedly showing a part fixingthe second end portion 162 of the suspension wire 16 to the upper leafspring 32. FIG. 39 is a partial cross sectional view of the fixed part.FIG. 40 is a plan view showing a state where the shielding cover 42 isomitted from the lens holder driving device 10A.

In the above-mentioned lens holder driving device 10 according to thefirst exemplary embodiment, the magnet holder 30 comprises the fourextending portions 310 which extend at the four corners thereof in theradial direction outwards as shown in FIGS. 19, 20, and 22.

In comparison with this, as shown in FIGS. 38, 39, and 40, in the lensholder driving device 10A according to the second exemplary embodiment,the magnet holder 30A does not comprise such four extending portions310. As a substitute for this, the outer tubular portion 302 of themagnet holder 30A has four guide grooves 302 a.

Referring to FIGS. 41 through 43, the description will proceed to amethod of mounting the four damper compounds 65 and positioning thereofthat is for suppressing undesired resonance in the direction θ of theoptical axis O of the auto-focusing lens holder driving portion (the AFunit) 20A in the lens holder driving device 10A.

FIG. 41 is a fragmentary vertical sectional view showing a state wherethe shielding cover 42 is omitted from the lens holder driving device10A. FIG. 42 is a fragmentary perspective view of the lens holderdriving device 10A illustrated in FIG. 41 seen from a slanting above.FIG. 43 is a plan view showing arrangement positions of the four dampercompounds 65 in the lens holder driving device 10A with a part of theupper leaf spring (the first leaf spring) 32 omitted therefrom.

The four damper compounds 65 are disposed between the four lowerprotrusions 306 a of the magnet holder 30A and the coil board 40. Theouter tubular portion 302 of the magnet holder 30A has theabove-mentioned four guide grooves 302 a for guiding a dispenser (notshown) for applying the four damper compounds 65. With this structure,it is possible to easily apply the four damper compounds 65 to theclearances between the four lower protrusions 306 a and the coil board40 by using the dispenser. In the manner which is described above, theclearances between the four lower protrusions 306 a and the coil board40 becomes narrow in comparison with clearance in the other areas.Accordingly, when the four damper compounds 65 are applied near the fourlower protrusions 306 a using the dispenser inserted along the guidegroove 302 a, the applied four damper compounds 65 naturally gather theclearances between the four lower protrusions 306 a and the coil board40 by the surface tension.

In the example being illustrated, as each damper compounds 65, anultraviolet cure silicone gel having viscosity of 90 Pa·s is used thatis sold by a product name of TB3168E made in ThreeBond Co., Ltd.

Accordingly, after the four damper compounds 65 are applied to theclearances between the four lower protrusions 306 a of the magnet holder30A and the coil board 40 in the manner which is described above, thefour damper compounds 65 are cured by irradiating the four dampercompounds 65 with ultraviolet.

Referring to FIGS. 44 and 45, the description will proceed to frequencyresponses in a case where the four damper compounds 65 are absent (priorart example) and in a case where the four damper compounds 65 arepresent (the second exemplary embodiment). FIG. 44 is a view showing afrequency response of the auto-focusing lens driving portion (the AFunit) 20A of a conventional lens holder device without the four dampercompounds 65 in the direction of the optical axis O while FIG. 45 is aview showing a frequency response of the auto-focusing lens drivingportion (AF unit) 20A of the lens holder driving device 10A according tothe first exemplary embodiment of the present invention with the fourdamper compounds 65 in the directions of the optical axis O. In each ofFIGS. 44 and 45, the abscissa presents a frequency [Hz] while theordinate represents a gain [dB].

As is apparent from FIG. 44, in the conventional lens holder drivingdevice without the damper compounds 65, it is understood that undesiredresonance (a higher resonance mode) of the auto-focusing lens holderdriving portion (the AF unit) 20 is generated at frequencies of about400 Hz in the direction of the optical axis O.

In contrast with this, as is apparent from FIG. 45, in the lens holderdriving device 10A according to the second exemplary embodiment with thefour damper compounds 65, it is understood that generation of suchundesired resonance (the higher resonance mode) in the direction of theoptical axis O is suppressed.

Accordingly, the lens holder driving device 10A according to the secondexemplary embodiment can carry out a stable control operation forstabilizing blurred images.

In addition, inasmuch as the four damper compounds 65 are disposed so asto support the auto-focusing lens holder driving portion (the AF unit)20A serving as a movable part at a side for stabilizing blurred images,it also has an effect which can relief impact to the auto-focusing lensholder driving portion (the AF unit) 20A on a drop of the lens holderdriving device 10A.

The above-mentioned lens holder driving device 10A according to thesecond exemplary embodiment of the present invention has effects whichwill be presently described.

First, it is possible for the two Hall elements 50 f and 501 to avoid adetrimental effect caused by the magnetic field generated by the currentflowing through the specific two image stabilizer coil portions 18 f and18 l because the two Hall elements 50 f and 501 are disposed on the base14 at the positions where the specific two image stabilizer coilportions 18 f and 18 l are separated into the respective two coil parts18 f 1, 18 fr and 18 lf, 18 lb.

Secondly, it is possible to prevent the four suspension wires 15 fromfracturing and to heighten impact resistance of the lens holder drivingdevice 10A because the lens holder driving device 10A comprises fracturepreventing member 328.

Thirdly, it is possible to electrically connect the inner wiring of theflexible printed circuit (FPC) 44 with the plurality of lands 18 a ofthe coil board 40 by means of solder reflow because the notch portions44 b are formed to the flexible printed circuit (FPC) 44 at thepositions corresponding to the plurality of lands 18 a formed on thecoil board 40.

Fourthly, it is possible to make the stoke in the case of positionadjusting the lens holder 24 (the lens barrel) in the direction of theoptical axis O larger because the height of the focusing coil 26 islower than the height of the permanent magnet piece 282.

Fifthly, it is possible to enhance sensitivity of the driving force formoving the auto-focusing lens holder driving portion (the AF unit) 20Aas a whole in the direction orthogonal to the optical axis O because thepermanent magnet pieces 282 and the image stabilizer coil 18 aredisposed so that the edges of the permanent magnet pieces in the radialdirection are laid in the coil sectional width of the image stabilizercoil 18 in the radial direction.

Sixthly, it is possible to suppress undesired resonance of theauto-focusing lens holder driving portion 20A and it is possible tocarry out a stable operation because the damper compounds 65 aredisposed between the fixed member 13 and the auto-focusing lens holderdriving portion 20A.

Seventhly, it possible to improve proof stress of the lens holderdriving device 10A on dropping because the damper compounds 65 aredisposed between the fixed member 13 and the auto-focusing lens holderdriving portion 20A.

Modified Examples

Now, the description will proceed to modified examples of the lensholder driving device 10A according to the second exemplary embodiment.

Although the four damper compounds 65 are provided at the four locationsas shown in FIG. 43 in the above-mentioned lens holder driving device10A according to the second exemplary embodiment, the number of thedamper compounds 65 and configuration thereof are not important in thisinvention, it is therefore important that the damper compound 65 isdisposed between a movable portion (the auto-focusing lens holderdriving portion) 20A and the fixed member 13.

By way of illustration, one damper compound 65 may be provided at onlyone location as the lens holder driving device 10A according to a firstmodified example in the manner as illustrated in FIG. 46. In addition,three damper compounds 65 may be provided at three locations as the lensholder driving device 10A according to a second modified example in themanner as illustrated in FIG. 47. Furthermore, eight damper compounds 65may be provided at eight locations as the lens holder driving device 10Aaccording to a third modified example in the manner as illustrated inFIG. 48.

In the manner which is described above, by proving one or plural dampercompounds 65 at one or plural locations as well, effects similar tothose of the above-mentioned second exemplary embodiment are obtained.

In the above-mentioned lens holder driving device 10A according to thesecond exemplary embodiment, the guide grooves 302 a are formed in themagnet holder 30A in order to easily apply the damper compounds 65 asshown in FIGS. 41 and 42. However, it may devoid of the guide grooves302 a as the lens holder driving device 10A according to a fourthmodified example in the manner as illustrated in FIG. 49.

Although the ultraviolet cure silicone gel is used as the dampercompound 65 in the above-mentioned lens holder driving device 10Aaccording to the second exemplary embodiment, material of the dampercompound 65 is not limited thereto, and may use any material having adamper effect.

Third Exemplary Embodiment

Referring to FIGS. 50 and 51, the description will proceed to a lensholder driving device 10B according to a third exemplary embodiment ofthe present invention. FIG. 50 is a vertical cross sectional view of thelens holder driving device 10B. FIG. 51 is an exploded perspective viewof the lens holder driving device 10B.

Herein, in the manner shown in FIGS. 50 and 51, an orthogonal coordinatesystem (X, Y, Z) is used. In a state illustrated in FIGS. 50 and 51, inthe orthogonal coordinate system (X, Y, X), an X-axis direction is afore-and-aft direction (a depth direction), a Y-axis direction is aleft-and-right direction (a width direction), and a Z-axis direction isan up-and-down direction (a height direction). In addition, in theexample being illustrated in FIGS. 50 and 51, the up-and-down directionZ is a direction of an optical axis O of a lens. In the third exemplaryembodiment, the X-axis direction (the fore-and-aft direction) is calleda first direction while the Y-axis direction (the left-and-rightdirection) is called in a second direction.

However, in an actual use situation, the direction of the optical axisO, namely, the Z-axis direction becomes a fore-and-aft direction. Inother words, an upper direction of the Z-axis becomes a front directionwhile a lower direction of the Z-axis becomes a rear direction.

The illustrated lens holder driving device 10B includes an auto-focusinglens holder driving portion 20B and an image stabilizer portion forstabilizing blurry images produced in the auto-focusing lens holderdriving portion 20B on shooting a still image using a miniature camerafor a mobile terminal and is a device which can pick up the still imagefree from image blurred.

The illustrated lens holder driving device 10B has a structure in whichthe lens holder driving device 10A according to the above-mentionedsecond exemplary embodiment is substantially turned upside down.Accordingly, it is suitable to change “upper” into “lower” and to change“lower” into “upper”. In order to simplify the description, the samereference signs are attached to those having functions similar those ofthe lens holder driving device 10A according to the second exemplaryembodiment and the description will later be made as regards onlydifferences.

The lend barrel 12 has a shape like a hanging bell. In place of theshielding cover 42, a shielding wall 422A having a rectangular tubularshape and a second base (a cover) 424A are used. In the auto-focusinglens holder driving portion (an AF unit) 20B, a spacer 36A is mounted tothe lower leaf spring 32 serving as a first leaf spring.

A configuration except for those is similar to the above-mentioned lensholder driving device 10A according to the second exemplary embodiment.

That is, damper compounds (not shown) are disposed between the fixedmember 13 and the auto-focusing lens holder driving portion (the AFunit) 20B serving as the movable portion.

Accordingly, the lens holder driving device 10B according to the thirdexemplary embodiment of the present invention has effects similar tothose of the above-mentioned lens holder driving device 10A according tothe second exemplary embodiment.

While this invention has been particularly shown and described withreference to the exemplary embodiments thereof, the invention is notlimited to the embodiment. It will be understood by those of ordinaryskill in the art that various changes in form and details may be thereinwithout departing from the spirit and scope of the present invention asdefined by the claims.

For example, although the four suspension wires 16 are used as thesupporting member for swingably supporting the auto-focusing lens holderdriving portion (the lens holder moving portion) with respect to thefixed member in the above-mentioned exemplary embodiments, the number ofthe suspension wires is not limited to four and therefore may be two ormore. In addition, although the first leaf spring 32 for supporting thelens holder 24 in the direction of the optical axis O shiftably so as toposition the lens holder 24 in the radial direction doubles as theelastic member which is mounted to the lens holder moving portion (26;28; 30) and to which the damper compounds 65 are applied in theabove-mentioned first exemplary embodiment, a spring member expresslymeant for preventing the suspension wires 16 from rupturing may be usedof course as a different part of the first leaf spring 32. Furthermore,although the protrusions 306 a are provided to the magnet holder 30A inthe above-mentioned second embodiment, as a substitute for this, it mayadopt a configuration in which concave portions or convex portions areprovided on the coil board 40 to stay the damper compounds in locationsthereof.

The whole or part of the exemplary embodiments disclosed above can bedescribed as, but not limited to, the following supplementary notes.

(Supplementary Note 1)

A lens holder driving device (10) comprising:

a lens holder moving portion (26; 28; 30) in which a lens holder (24)moves in a direction of an optical axis (O) and in first and seconddirections (X, Y) which are orthogonal to the optical axis (O) and whichare perpendicular to each other; and

a fixed member (13) disposed apart from said lens holder moving portionin the direction of the optical axis (O),

wherein said lens holder driving device (10) comprises:

an elastic member (32, 34) mounted to said lens holder moving portion(26; 28; 30);

a plurality of suspension wires (16) having first end portions (161)fixed to said fixed member (13) at outer regions thereof, said pluralityof suspension wires (16) extending along the optical axis (O) and havingsecond end portions (162) fixed to said elastic member (32), saidplurality of suspension wires (16) swingably supporting said lens holdermoving portion (26; 28; 30) in the first direction (X) and the seconddirection (Y); and

at least one damper compound (65) disposed so as to enclose at least onesuspension wire among said plurality of suspension wires, said dampercompound (65) suppressing undesired resonance in said lens holder movingportion (26; 28; 30).

(Supplementary Note 2)

The lens holder driving device according to Supplementary note 1,wherein said lens holder moving portion (26; 28; 30) has first andsecond ends (30 a, 30 b) opposite to each other in the direction of theoptical axis (O),

wherein said elastic member comprises first and second leaf springs (32,34), mounted to the first and the second ends (30 a, 30 b) of said lensholder moving portion (26; 28; 30), respectively, supporting said lensholder (24) in the direction of the optical axis (O) shiftably,

wherein said fixed member (13) is disposed at a position in the vicinityof said second leaf spring (34),

wherein the second end portions (162) of said at least one suspensionwire (16) is fixed to said first leaf spring (32) at a wire fixingportion (328) thereof.

(Supplementary Note 3)

The lens holder driving device according to Supplementary note 2,wherein said lens holder moving portion (26; 28; 30) comprises anextending portion (310) extending so as to enclose said at least onesuspension wire (16) with a space at a position in the vicinity of saidwire fixing portion (328),

wherein said at least one damper compound (65) is disposed in saidextending portion (310) so as to enclose said at least one suspensionwire (16).

(Supplementary Note 4)

The lens holder driving device according to Supplementary note 1,wherein said fixed member (13) comprises:

a base (14); and

a coil board (40) fixed on said base (14), said coil board (40) fixingthe first end portions (161) of said plurality of suspension wires (16)at the outer regions thereof and including a driving coil (18) drivingsaid lens holder moving portion (26; 28; 30) formed thereon,

wherein said driving coil (18) comprises driving coil portions (18 f, 18b, 18 l, 18 r) mounted on said coil board (40) so as to oppose topermanent magnet pieces (mounted to said lens holder moving portion (26;28; 30).

(Supplementary Note 5)

A camera module (70) comprising the lens holder driving device (10)according to Supplementary note 1, a lens barrel (12) held in said lensholder (24), and an image pickup device (76) picking up a subject imageformed by said lens barrel (12).

(Supplementary Note 6)

A camera-equipped mobile terminal (80) in which the camera module (70)according to Supplementary note 5 is mounted.

(Supplementary Note 7)

A lens holder driving device (10A; 10B) comprising:

an auto-focusing lens holder driving portion (20A; 20B) moving a lensholder (24) holding a lens barrel (12) along an optical axis (O); and

an image stabilizer portion stabilizing image blurred by moving saidauto-focusing lens holder driving portion (20A; 20B) in first and seconddirections (X, Y) which are orthogonal to the optical axis (O) and whichare perpendicular to each other,

wherein said image stabilizer portion comprises:

a fixed member (13) disposed apart from said auto-focusing lens holderdriving portion (20A; 20B) in the direction of the optical axis (O);

a plurality of suspension wires (16) having first end portions (161)fixed to said fixed portion (13) at outer regions thereof, saidplurality of suspension wires (16) extending along the optical axis (O)and having second end portions (162) fixed to said auto-focusing lensholder driving portion (20A; 20B), said plurality of suspension wires(16) swingably supporting said auto-focusing lens holder driving portion(20A; 20B) in the first direction (X) and the second direction (Y); and

at least one damper compound (65) disposed between said auto-focusinglens holder driving portion (20A; 20B) and said fixed member (13), saidat least one damper compound (65) suppressing undesired resonance ofsaid auto-focusing lens holder driving portion (20A; 20B) in thedirection of the optical axis (O).

(Supplementary Note 8)

The lens holder driving device according to Supplementary note 7,wherein said auto-focusing lens holder driving portion (20A; 20B)comprises:

a focusing coil (26) fixed to said lens holder (24);

a permanent magnet (28) comprising four permanent magnet pieces (282 f,282 b, 2821, 282 r) which have first surfaces opposed to said focusingcoil (26) and which are disposed outsides of said focusing coil (26)with respect to the optical axis (O) in a radial direction so as tooppose to each other in the first direction (X) and the second direction(Y);

a magnet holder (30), disposed around the periphery of said lens holder(24), holding said permanent magnet (28), said magnet holder (30) havingfirst and second ends (30 a, 30 b) opposite to each other in thedirection of the optical axis (O); and

first and second leaf springs (32, 34), mounted to the first and thesecond ends (30 a, 30 b) of said magnet holder (30), supporting saidlens holder (24) in the direction of the optical axis (O) shiftably soas to position said lens holder (24) in the radial direction,

wherein said fixed member (13) is disposed at a position in the vicinityof said second leaf spring (34),

wherein the second end portions (162) of said plurality of suspensionwires (162) are fixed to said first leaf spring (32) at wire fixingportions (328) thereof;

wherein said magnet holder (30A) has at least one protrusion (306 a)projecting toward said fixed member (13),

wherein said at least one damper compound (65) is disposed between saidprotrusion (306 a) and said fixed member (13).

(Supplementary Note 9)

The lens holder driving device according to Supplementary note 8,wherein said protrusion (306 a) projects toward said fixed member (13)via a hole (344 a) formed in said second leaf spring (34).

(Supplementary Note 10)

The lens holder driving device according to Supplementary note 8,wherein said fixed member (13) comprises:

a base (14); and

a coil board (40) fixed on said base (14), said coil board (40) fixingthe first end portions (161) of said plurality of suspension wires (16)at the outer regions thereof and including an image stabilizer coil (18)of said image stabilizer portion formed thereon,

wherein said at least one damper compound (65) is disposed between saidprotrusion (306 a) and said coil board (40).

(Supplementary Note 11)

The lens holder driving device according to Supplementary note 10,wherein said image stabilizer coil (18) comprising four image stabilizercoil portions (18 f, 18 b, 18 l, 18 r) mounted on said coil board (40)so as to oppose to second surfaces of said four permanent magnet pieces(282 f, 282 b, 2821, 282 r) that are perpendicular of to the firstsurfaces.

(Supplementary Note 12)

The lens holder driving device according to Supplementary note 8,wherein said magnet holder (30A) has a guide groove (302 a) guiding adispenser for applying said at least one damper compound (65).

In this connection, inasmuch as reference signs in parentheses areattached in order to facilitate an understanding of this invention andare merely one example thereof, this invention is, of course, notlimited to them.

What is claimed is:
 1. A lens drive apparatus comprising: anauto-focusing lens driving section that moves a lens barrel along anoptical axis; and an image stabilizer section that stabilizes an imageby moving the auto-focusing lens driving section along first and seconddirections that are orthogonal to the optical axis and perpendicular toeach other, wherein the image stabilizer section comprises: a fixedmember disposed apart from the auto-focusing lens driving section in thedirection of the optical axis; a plurality of suspension wires that havefirst end portions fixed to the fixed member at outer regions thereof,that extend along the optical axis, that have second end portions fixedto the auto-focusing lens driving section, and that support theauto-focusing lens driving section swingably in the first and seconddirections; a fracture preventing member that prevents the plurality ofsuspension wires from fracturing; and a cover that covers theauto-focusing lens driving section at an opposite side of the fixedmember, the auto-focusing lens driving section comprises: a lens holderthat has a tubular section that holds the lens barrel; a focusing coilfixed to the lens holder such that the focusing coil is positioned on acircumference of the tubular section; a permanent magnet disposed toface the focusing coil; a magnet holder, disposed around the lensholder, that holds the permanent magnet; first and second leaf springs,attached to first and second ends of the magnet holder in the directionof the optical axis, respectively, the second leaf spring being disposedat a position in the vicinity of the fixed member compared to the firstleaf spring, the first and second leaf springs together supporting thelens holder in the direction of the optical axis shiftably to positionthe lens holder in a radial direction, and a plurality of protrusionsprotruding from the first end of the magnet holder in the direction ofthe optical axis toward an inner wall surface of the cover, thatfunctions as a fracture prevention supporting member that supportsprevention of fracture in the plurality of suspension wires, the lensdrive apparatus further comprises: a damper compound, disposed betweenthe at least one protrusion and the fixed member so as to enclose atleast one suspension wire among the plurality of suspension wires, thatsuppresses undesired resonance of the auto-focusing lens driving sectionin the direction of the optical axis, the second end portions are fixedto the first leaf spring, the first leaf spring includes a deformable,extending portion extending around the plurality of protrusions whichare partly provided with a wire fixing portion to which the second endof the plurality of suspension wires is fixed, the extending portion andthe wire fixing portion functioning as the fracture preventionsupporting member, and the plurality of protrusions are configured tosupport prevention of fracture in the plurality of suspension wires bycontacting the inner wall surface of the cover when the magnet holdermoves in the direction of the optical axis.
 2. The lens drive apparatusas claimed in claim 1, wherein the fixed member comprises: a base whichfixes, at the outer regions thereof, the first end portions of theplurality of suspension wires; and a coil board that is fixed on thebase and provided with a driving coil that drives the auto-focusing lensdriving section, and the driving coil comprises a driving coil sectiondisposed on the coil board so as to face a permanent magnet piece of thepermanent magnet held by the magnet holder.
 3. A camera modulecomprising the lens drive apparatus as claimed in claim 1; a lens barrelheld by the lens holder; and an image pickup device that picks up asubject image formed by the lens barrel.
 4. A camera comprising thecamera module as claimed in claim 3.